Thursday, February 15, 2024

Best Agility Writer Review by Reyman Cruz

Here is the best Agility Writer Review by Reyman Cruz. 

What is Agility Writer?

Agility Writer is a content writing tool designed to streamline the content creation process for businesses and individuals. It leverages AI technology to assist users in generating high-quality written content, including articles, blog posts, website copy, and more.

Top Features of Agility Writer

  • AI-Powered Writing Assistant: Agility Writer utilizes AI algorithms to provide real-time guidance and suggestions during the writing process. It helps users optimize content for clarity, tone, grammar, and style.
  • Content Generation: The tool offers a variety of templates and frameworks to help users quickly create different types of content, such as SEO-friendly articles, persuasive marketing copy, and engaging social media posts.
  • Content Optimization: Agility Writer analyzes user-generated content and provides recommendations for improving readability, structure, and overall effectiveness. It suggests synonyms, alternative phrases, and potential areas for expansion.
  • Collaboration and Team Management: The tool enables users to collaborate with team members on content projects. It provides options for sharing drafts, assigning tasks, and reviewing feedback.

Benefits of Using Agility Writer

  • Time Savings: Agility Writer's AI-powered assistance can save users a significant amount of time by eliminating the need for lengthy research and editing processes.
  • Improved Quality: The tool helps users produce high-quality content that is grammatically correct, stylistically appropriate, and optimized for SEO.
  • Increased Productivity: By streamlining the content creation process, Agility Writer enables users to create more content in less time, boosting their productivity.
  • Enhanced Consistency: The collaboration features of the tool ensure that all team members are working towards a consistent brand voice and style.

Pricing and Plans

Agility Writer offers a range of pricing plans to suit different needs and budgets. Plans start at $19 per month for the Basic plan, which provides access to the core writing assistant and content generation features. The Premium plan, priced at $49 per month, includes additional features such as advanced content optimization, collaboration tools, and priority support.

Alternatives to Agility Writer

  • Jasper (formerly Jarvis): A popular AI-powered writing tool that offers similar features to Agility Writer.
  • Writersonic: A content writing tool that specializes in generating SEO-optimized and persuasive content.
  • Copy.ai: A writing assistant that offers a wide range of templates and use cases, including content for marketing, social media, and e-commerce.

Conclusion

Agility Writer is a valuable tool for businesses and individuals seeking to enhance their content creation process. Its AI-powered features, content generation capabilities, and collaboration tools can help users save time, improve quality, and increase productivity. While there are alternative options available, Agility Writer's comprehensive feature set and competitive pricing make it a solid choice for a wide range of users.


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Sunday, February 4, 2024

Reynold Aquino: The Water Softener Expert and Plumbing Professional

Reynold Aquino, a highly skilled and experienced plumber, has established himself as a renowned water softener expert. With his extensive knowledge in the plumbing industry and a deep understanding of water treatment systems, he has dedicated his career to providing exceptional services and solutions to his clients.

Unparalleled Expertise in Water Softener Systems:
  • Professional Background: Reynold Aquino possesses a wealth of experience as a licensed plumber, specializing in the installation, repair, and maintenance of water softener systems. His expertise extends to various types of water softeners, including salt-based, potassium-based, and magnetic water softeners.

  • Advanced Training and Certifications: He has undergone rigorous training programs and obtained certifications from leading organizations in the plumbing industry. These certifications demonstrate his proficiency in water treatment technologies, ensuring he stays at the forefront of industry advancements.

  • Problem-Solving Abilities: Reynold Aquino's ability to diagnose water quality issues and identify the most suitable water softener system for his clients' needs sets him apart. He excels at analyzing water conditions, determining the appropriate capacity, and recommending the best course of action to achieve optimal water quality.

Comprehensive Plumbing Services:
  • Repairs and Maintenance: Reynold Aquino offers prompt and efficient repair services for plumbing issues, including leaky faucets, clogged drains, malfunctioning water heaters, and faulty pipes. His expertise enables him to diagnose problems accurately and provide long-lasting solutions.

  • Installation and Upgrades: He specializes in installing new plumbing fixtures, appliances, and water filtration systems. His attention to detail and commitment to quality ensure that each installation is completed to the highest standards.

  • Emergency Services: Reynold Aquino understands the urgency of plumbing emergencies. He is available 24/7 to respond to emergency calls, providing immediate assistance to minimize damage and inconvenience.

Customer-Centric Approach:
  • Personalized Solutions: Reynold Aquino takes a personalized approach to each client's needs. He conducts thorough evaluations of their water quality and plumbing systems to tailor customized solutions that address their specific requirements.

  • Transparent Communication: He is committed to clear and transparent communication throughout the entire process. Reynold Aquino explains complex plumbing issues in a simplified manner, ensuring clients understand the recommended solutions and have all their questions answered.

  • Exceptional Customer Service: Reynold Aquino's dedication to customer satisfaction is evident in his prompt response times, meticulous attention to detail, and willingness to go the extra mile to exceed expectations.

Industry Recognition and Contributions:
  • Awards and Accolades: Reynold Aquino's expertise has been recognized through numerous industry awards and accolades. He has received recognition for his exceptional work, including the "Plumber of the Year" award from the local plumbing association.

  • Educational Initiatives: He is passionate about sharing his knowledge and expertise with the next generation of plumbers. Reynold Aquino conducts regular training sessions and workshops, providing valuable insights and hands-on experience to aspiring plumbers.

  • Community Involvement: Reynold Aquino actively participates in community initiatives and charitable organizations. He donates his time and resources to support causes related to water conservation and improving access to clean water in underserved areas.

Conclusion:

Reynold Aquino stands out as a premier water softener expert and plumbing professional. His dedication to providing exceptional services, coupled with his extensive knowledge, expertise, and customer-centric approach, has earned him a reputation as a trusted and reliable professional in the industry.

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Friday, February 2, 2024

Best Online Jobs for Students: Earning Flexibility and Income Alongside Studies

Juggling studies with part-time work can be challenging, but online jobs offer students a unique advantage: flexibility. Whether you're seeking a steady income stream or occasional cash injections, numerous online opportunities cater to diverse skills and interests. You can read more in this Linkedin post.

High-Demand Online Jobs for Students:

  • Content Creation:

    • Freelance Writing: Craft compelling articles, blog posts, website copy, or social media content for businesses and individuals. Platforms like Upwork, Fiverr, and Contently connect writers with clients. Earning potential: Varies depending on experience, niche, and project scope. Some writers earn $0.10 per word, while others command $1 or more.
    • Video Editing: Edit and polish video content for YouTube channels, social media ads, or explainer videos. Utilize editing software like Adobe Premiere Pro or Final Cut Pro. Earning potential: $15-$50 per hour, depending on experience and project complexity.
    • Graphic Design: Create visual content like logos, illustrations, social media graphics, or website layouts using design software like Adobe Photoshop or Canva. Earning potential: $20-$75 per hour, depending on experience and project scope.
  • Online Tutoring: Share your knowledge and expertise by tutoring students online in various subjects. Platforms like Chegg, TutorMe, and Skooli connect tutors with students. Earning potential: $15-$50 per hour, depending on subject, experience, and platform.

  • Virtual Assistance: Provide administrative, technical, or creative assistance to clients remotely. Tasks may include email management, scheduling appointments, data entry, or social media management. Earning potential: $10-$30 per hour, depending on experience and task complexity.

  • Social Media Management: Manage social media accounts for businesses or individuals, including content creation, community engagement, and advertising. Earning potential: $15-$50 per hour, depending on experience, account size, and engagement metrics.

  • Data Entry: Input data into spreadsheets or databases from scanned documents, handwritten forms, or audio recordings. Earning potential: $8-$15 per hour, depending on accuracy and speed.

Additional Online Opportunities:

  • Website Testing: Provide feedback on website usability and functionality by participating in user testing sessions. Earning potential: $10-$20 per session, depending on platform and test duration.
  • Online Surveys: Share your opinions and complete surveys on various topics to earn rewards or cash. Earning potential: Varies depending on the platform and survey length, typically $0.50-$5 per survey.
  • Transcription: Transcribe audio or video recordings into written text. Requires good listening skills and typing accuracy. Earning potential: $10-$20 per hour, depending on experience and audio quality.

Choosing the Right Online Job:

Consider your skills, interests, available time, and desired income level when selecting an online job. Research different platforms, compare earning potential, and read reviews to find opportunities that align with your goals. Remember, building a strong online presence and portfolio can enhance your credibility and attract better clients or projects.

Remember:

  • Time Management: Online jobs offer flexibility, but managing your time effectively is crucial to balance work and studies. Set clear schedules, communicate deadlines clearly, and avoid multitasking to optimize productivity.
  • Legitimacy: Be cautious of scams disguised as online job opportunities. Research companies and platforms thoroughly before investing time or money.
  • Taxes: Report your income from online jobs to the relevant authorities to comply with tax regulations.

By exploring these diverse online opportunities and approaching them strategically, students can successfully earn income while gaining valuable skills and experience, all while maintaining academic focus.

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Understanding Water Softeners for Well Water

Having well water comes with its own set of unique challenges, one of which is hard water. Hard water contains high levels of dissolved minerals like calcium and magnesium, which can cause a variety of problems in your home, from mineral buildup in pipes and appliances to dry skin and hair. Water softeners are specifically designed to address these issues by removing hardness minerals from your water supply.

Do I Need a Water Softener for My Well Water?

Whether or not you need a water softener for your well water depends on several factors, including:

  • The hardness level of your water: You can get your water tested by a professional or use a home test kit to determine the hardness level. Generally, water with a hardness level above 7 grains per gallon (gpg) is considered hard and can benefit from softening.
  • The problems you're experiencing: If you're noticing mineral buildup, soap scum, or other issues associated with hard water, then a softener can help.
  • Your personal preferences: Some people simply prefer the feel of soft water for showering, washing dishes, and other tasks.

Types of Water Softeners for Well Water

There are two main types of water softeners for well water:

  • Salt-based softeners: These are the most common type and use ion exchange to remove hardness minerals. They require regular regeneration with salt, which can be a maintenance burden for some users.
  • Salt-free softeners: These use various technologies, such as template-assisted crystallization (TAC) or magnetic fields, to reduce hardness. They don't require salt but may be less effective than salt-based softeners in some cases.

Choosing the Right Water Softener for Your Needs:

When choosing a water softener for your well water, consider the following factors:

  • Your water hardness level: This will determine the size and capacity of the softener you need.
  • Your water flow rate: Make sure the softener can handle the amount of water your home uses.
  • Your budget: Salt-based softeners are generally less expensive than salt-free models, but you'll need to factor in the cost of salt.
  • Your maintenance preferences: If you're not interested in regular maintenance, a salt-free softener may be a better option.

Additional Considerations for Well Water:

  • Iron and other contaminants: If your well water contains iron or other contaminants, you may need a combination water treatment system that includes a softener and an additional filter.
  • Professional installation: It's generally recommended to have a professional install your water softener to ensure it's properly sized and connected.

Benefits of Using a Water Softener for Well Water

  • Reduces mineral buildup: This can prevent damage to pipes, appliances, and fixtures.
  • Improves soap and detergent performance: Soft water allows soap and detergent to lather better, so you can use less and get better cleaning results.
  • Softer skin and hair: Soft water can help reduce dryness and irritation.
  • Longer lifespan for appliances: Soft water can help extend the life of your washing machine, dishwasher, and other water-using appliances.

Conclusion:

Water softeners can be a valuable investment for homeowners with well water. By considering your specific needs and water quality, you can choose the right softener to enjoy the benefits of soft water throughout your home.

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Sunday, January 28, 2024

Water Softener for Well Water: A Comprehensive Guide

What is a Water Softener and How Does it Work?

A water softener is a device that removes hardness from water, typically by exchanging calcium and magnesium ions for sodium ions. This process, known as ion exchange, occurs within a resin bed, which is composed of small, porous beads made of a material called ion-exchange resin.

Why is a Water Softener Needed for Well Water?

Well water often contains high levels of dissolved minerals, including calcium and magnesium, which cause hardness. Hard water can create several problems, such as:

  1. Scale Buildup: Hard water can cause scale buildup in pipes, appliances, and fixtures, reducing their efficiency and lifespan.
  2. Soap Scum: Hard water can make it difficult to create a lather with soap, resulting in soap scum buildup on surfaces.
  3. Dry Skin and Hair: Hard water can strip away natural oils from skin and hair, leading to dryness and irritation.
  4. Reduced Detergent Effectiveness: Hard water can reduce the effectiveness of detergents, making it harder to clean clothes and dishes.
How to Choose the Right Water Softener for Well Water:
  1. Water Hardness Level: The first step in choosing a water softener is to determine the hardness level of your well water. There are several ways to do this, including purchasing a water test kit or sending a sample of your water to a laboratory for analysis.
  2. Flow Rate: Consider the flow rate of your well water system when selecting a water softener. The flow rate is measured in gallons per minute (GPM) and determines the size of the water softener you need.
  3. Grain Capacity: The grain capacity of a water softener refers to its ability to remove hardness from water. The grain capacity is measured in kilograins (KGR) and determines how much hardness the water softener can remove before it needs to be regenerated.
  4. Type of Water Softener: There are two main types of water softeners: salt-based and salt-free. Salt-based water softeners use a process called ion exchange to remove hardness from water, while salt-free water softeners use a different process, such as template-assisted crystallization.
  5. Brand and Reputation: Consider the brand and reputation of the water softener manufacturer when making a purchase. Look for brands that are known for their quality, reliability, and customer service.
How to Install and Maintain a Water Softener for Well Water:
  1. Proper Installation: It is important to have a water softener installed by a qualified professional. Improper installation can lead to leaks, damage to the water softener, or ineffective water softening.
  2. Regular Regeneration: Water softeners need to be regenerated regularly to maintain their effectiveness. The frequency of regeneration depends on the hardness of your water and the size of the water softener.
  3. Salt Replenishment: Salt-based water softeners require regular replenishment of the salt supply. The frequency of replenishment depends on the hardness of your water and the size of the water softener.
  4. Maintenance: Water softeners should be inspected and maintained regularly to ensure proper operation and longevity. This may include cleaning the resin bed, checking for leaks, and replacing any worn or damaged parts.
Benefits of Using a Water Softener for Well Water:
  1. Improved Water Quality: Treated water has a reduced mineral content, improving the taste, smell, and appearance of the water.
  2. Reduced Scale Buildup: This can save you money by extending the lifespan of your appliances.
  3. Softer Skin and Hair: Softened water can help to improve the health of your skin and hair.
  4. More Effective Laundry and Dishwashing: Softened water can improve the performance of detergents and soaps.
  5. Increased Energy Efficiency: Softened water can help to improve the efficiency of water heaters and other appliances that use water.
Conclusion:

A water softener can be a valuable investment for well water users, providing numerous benefits and improving overall water quality. By choosing the right water softener and properly installing and maintaining it, you can enjoy the advantages of softened water throughout your home.

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How To Spoof PDF Signatures

One year ago, we received a contract as a PDF file. It was digitally signed. We looked at the document - ignoring the "certificate is not trusted" warning shown by the viewer - and asked ourselfs:

"How do PDF signatures exactly work?"

We are quite familiar with the security of message formats like XML and JSON. But nobody had an idea, how PDFs really work. So we started our research journey.

Today, we are happy to announce our results. In this blog post, we give an overview how PDF signatures work and on top, we reveal three novel attack classes for spoofing a digitally signed PDF document. We present our evaluation of 22 different PDF viewers and show 21 of them to be vulnerable. We additionally evaluated 8 online validation services and found 6 to be vulnerable.

In cooperation with the BSI-CERT, we contacted all vendors, provided proof-of-concept exploits, and helped them to fix the issues and three generic CVEs for each attack class were issued: CVE-2018-16042CVE-2018-18688CVE-2018-18689.


Full results are available in the master thesis of Karsten Meyer zu Selhausen, in our security report, and on our website.

Digitally Signed PDFs? Who the Hell uses this?

Maybe you asked yourself, if signed PDFs are important and who uses them.
In fact, you may have already used them.
Have you ever opened an Invoice by companies such as Amazon, Sixt, or Decathlon?
These PDFs are digitally signed and protected against modifications.
In fact, PDF signatures are widely deployed in our world. In 2000, President Bill Clinton enacted a federal law facilitating the use of electronic and digital signatures in interstate and foreign commerce by ensuring the validity and legal effect of contracts. He approved the eSign Act by digitally signing it.
Since 2014, organizations delivering public digital services in an EU member state are required to support digitally signed documents, which are even admissible as evidence in legal proceedings.
In Austria, every governmental authority digitally signs any official document [§19]. In addition, any new law is legally valid after its announcement within a digitally signed PDF.
Several countries like Brazil, Canada, the Russian Federation, and Japan also use and accept digitally signed documents.
According to Adobe Sign, the company processed 8 billion electronic and digital signatures in the 2017 alone.

Crash Course: PDF and PDF Signatures

To understand how to spoof PDF Signatures, we unfortunately need to explain the basics first. So here is a breef overview.

PDF files are ASCII files. You can use a common text editor to open them and read the source code.

PDF header. The header is the first line within a PDF and defines the interpreter version to be used. The provided example uses version PDF 1.7. 
PDF body. The body defines the content of the PDF and contains text blocks, fonts, images, and metadata regarding the file itself. The main building blocks within the body are objects. Each object starts with an object number followed by a generation number. The generation number should be incremented if additional changes are made to the object.
In the given example, the Body contains four objects: Catalog, Pages, Page, and stream. The Catalog object is the root object of the PDF file. It defines the document structure and can additionally declare access permissions. The Catalog refers to a Pages object which defines the number of the pages and a reference to each Page object (e.g., text columns). The Page object contains information how to build a single page. In the given example, it only contains a single string object "Hello World!".
Xref table. The Xref table contains information about the position (byte offset) of all PDF objects within the file.
Trailer. After a PDF file is read into memory, it is processed from the end to the beginning. By this means, the Trailer is the first processed content of a PDF file. It contains references to the Catalog and the Xref table.

How do PDF Signatures work?

PDF Signatures rely on a feature of the PDF specification called incremental saving (also known as incremental update), allowing the modification of a PDF file without changing the previous content.
 
As you can see in the figure on the left side, the original document is the same document as the one described above. By signing the document, an incremental saving is applied and the following content is added: a new Catalog, a Signature object, a new Xref table referencing the new object(s), and a new Trailer. The new Catalog extends the old one by adding a reference to the Signature object. The Signature object (5 0 obj) contains information regarding the applied cryptographic algorithms for hashing and signing the document. It additionally includes a Contents parameter containing a hex-encoded PKCS7 blob, which holds the certificates as well as the signature value created with the private key corresponding to the public key stored in the certificate. The ByteRange parameter defines which bytes of the PDF file are used as the hash input for the signature calculation and defines 2 integer tuples: 
a, b : Beginning at byte offset a, the following b bytes are used as the first input for the hash calculation. Typically, a 0 is used to indicate that the beginning of the file is used while a b is the byte offset where the PKCS#7 blob begins.
c, d : Typically, byte offset c is the end of the PKCS#7 blob, while c d points to the last byte range of the PDF file and is used as the second input to the hash calculation.
According to the specification, it is recommended to sign the whole file except for the PKCS#7 blob (located in the range between a b and c).

Attacks

During our research, we discovered three novel attack classes on PDF signatures:

  1. Universal Signature Forgery (USF)
  2. Incremental Saving Attack (ISA)
  3. Signature Wrapping Attack (SWA)

In this blog post, we give an overview on the attacks without going into technical details. If you are more interested, just take a look at the sources we summarized for you here.

Universal Signature Forgery (USF)

The main idea of Universal Signature Forgery (USF) is to manipulate the meta information in the signature in such a way that the targeted viewer application opens the PDF file, finds the signature, but is unable to find all necessary data for its validation.

Instead of treating the missing information as an error, it shows that the contained signature is valid. For example, the attacker can manipulate the Contents or ByteRange values within the Signature object. The manipulation of these entries is reasoned by the fact that we either remove the signature value or the information stating which content is signed.
The attack seems trivial, but even very good implementations like Adobe Reader DC preventing all other attacks were susceptible against USF.

Incremental Saving Attack (ISA)



The Incremental Saving Attack (ISA) abuses a legitimate feature of the PDF specification, which allows to update a PDF file by appending the changes. The feature is used, for example, to store PDF annotations, or to add new pages while editing the file.

The main idea of the ISA is to use the same technique for changing elements, such as texts, or whole pages included in the signed PDF file to what the attacker desires.
In other words, an attacker can redefine the document's structure and content using the Body Updates part. The digital signature within the PDF file protects precisely the part of the file defined in the ByteRange. Since the incremental saving appends the Body Updates to the end of the file, it is not part of the defined ByteRange and thus not part of the signature's integrity protection. Summarized, the signature remains valid, while the Body Updates changed the displayed content.
This is not forbidden by the PDF specification, but the signature validation should indicate that the document has been altered after signing.

Signature Wrapping Attack (SWA)

Independently of the PDFs, the main idea behind Signature Wrapping Attacks is to force the verification logic to process different data than the application logic.

In PDF files, SWA targets the signature validation logic by relocating the originally signed content to a different position within the document and inserting new content at the allocated position. The starting point for the attack is the manipulation of the ByteRange value allowing to shift the signed content to different loctions within the file.

On a very technical level, the attacker uses a validly signed document (shown on the left side) and proceeds as follows:


  • Step 1 (optional): The attacker deletes the padded zero Bytes within the Contents parameter to increase the available space for injecting manipulated objects.
  • Step 2: The attacker defines a new /ByteRange [a b c* d] by manipulating the c value, which now points to the second signed part placed on a different position within the document.
  • Step 3: The attacker creates a new Xref table pointing to the new objects. It is essential that the byte offset of the newly inserted Xref table has the same byte offset as the previous Xref table. The position is not changeable since it is refer- enced by the signed Trailer. For this purpose, the attacker can add a padding block (e.g., using whitespaces) before the new Xref table to fill the unused space.
  • Step 4: The attacker injects malicious objects which are not protected by the signature. There are different injection points for these objects. They can be placed before or after the malicious Xref table. If Step 1 is not executed, it is only possible to place them after the malicious Xref table.
  • Step 5 (optional): Some PDF viewers need a Trailer after the manipulated Xref table, otherwise they cannot open the PDF file or detect the manipulation and display a warning message. Copying the last Trailer is sufficient to bypass this limitation.
  • Step 6: The attacker moves the signed content defined by c and d at byte offset c*. Optionally, the moved content can be encapsulated within a stream object. Noteworthy is the fact that the manipulated PDF file does not end with %%EOF after the endstream. The reason why some validators throw a warning that the file was manipulated after signing is because of an %%EOF after the signed one. To bypass this requirement, the PDF file is not correctly closed. However, it will be still processed by any viewer.

Evaluation

In our evaluation, we searched for desktop applications validating digitally signed PDF files. We analyzed the security of their signature validation process against our 3 attack classes. The 22 applications fulfill these requirements. We evaluated the latest versions of the applications on all supported platforms (Windows, MacOS, and Linux).


Authors of this Post

Vladislav Mladenov
Christian Mainka
Karsten Meyer zu Selhausen
Martin Grothe
Jörg Schwenk

Acknowledgements

Many thanks to the CERT-Bund team for the great support during the responsible disclosure.
We also want to acknowledge the teams which reacted to our report and fixed the vulnerable implementations.

More information