How secure coding guidelines evolve
Last week I was researching vulnerabilities in Java Spring to bring our secure coding guidelines up to date. I was going through the existing challenges on our platform and noticed a few on XSS through displaying url parameters in JSP pages. The incorrect code example would look something similar to the following:
<input type="text" name="username" value="${param.username}">
The correct solution was removing the URL parameter altogether and the description mentions that escaping the URL parameter the correct way is also safe.
Now, my job is to formulate the secure coding guideline in a way that is clear to developers and restricts them as little as possible while still writing secure code. In this case, I would prefer to let developers keep their intended functionality and recommend them to do it securely by escaping the URL parameter. This way, the code no longer contains a XSS vulnerability. The above example can be secured like this:
<input type="text" name="username" value="${fn:escapeXml(param.username)}">
And this was our secure coding guideline for a few days, until I stumbled on an OWASP page on expression language injection. This page describes how the Spring Expression Language (SpEL) can be abused for injection with some serious impact, including remote code execution. It was up to me to figure out if there could be cases where code adhering to our secure coding guideline can still be affected by this vulnerability. So I wrote a quick test application to evaluate SpEL expressions, and tested input with and without Xml escaping to see if I could find some scenarios that would not be caught. And I did, there are malicious expressions that do not contain any characters caught by XmlEscape. I published the working demo on our github, which you can find here.
And of course I updated our secure coding guideline which now reads: "Do not display or evaluate URL parameters using the Spring Expression Language (SpEL)."
The overall impact of this issue is High, for the following reasons: - An attacker could modify and invoke functionality on the application server. - Unauthorized access to data and functionality, as well as account hijacking and remote code execution. - Confidentiality, and Integrity concerns from a successful attack.
https://www.owasp.org/index.php/Expression_Language_Injection
Last week I was researching vulnerabilities in Java Spring to bring our secure coding guidelines up to date.
Application Security Researcher - R&D Engineer - PhD Candidate
Secure Code Warrior is here for your organization to help you secure code across the entire software development lifecycle and create a culture in which cybersecurity is top of mind. Whether you’re an AppSec Manager, Developer, CISO, or anyone involved in security, we can help your organization reduce risks associated with insecure code.
Book a demo
Application Security Researcher - R&D Engineer - PhD Candidate
Last week I was researching vulnerabilities in Java Spring to bring our secure coding guidelines up to date. I was going through the existing challenges on our platform and noticed a few on XSS through displaying url parameters in JSP pages. The incorrect code example would look something similar to the following:
<input type="text" name="username" value="${param.username}">
The correct solution was removing the URL parameter altogether and the description mentions that escaping the URL parameter the correct way is also safe.
Now, my job is to formulate the secure coding guideline in a way that is clear to developers and restricts them as little as possible while still writing secure code. In this case, I would prefer to let developers keep their intended functionality and recommend them to do it securely by escaping the URL parameter. This way, the code no longer contains a XSS vulnerability. The above example can be secured like this:
<input type="text" name="username" value="${fn:escapeXml(param.username)}">
And this was our secure coding guideline for a few days, until I stumbled on an OWASP page on expression language injection. This page describes how the Spring Expression Language (SpEL) can be abused for injection with some serious impact, including remote code execution. It was up to me to figure out if there could be cases where code adhering to our secure coding guideline can still be affected by this vulnerability. So I wrote a quick test application to evaluate SpEL expressions, and tested input with and without Xml escaping to see if I could find some scenarios that would not be caught. And I did, there are malicious expressions that do not contain any characters caught by XmlEscape. I published the working demo on our github, which you can find here.
And of course I updated our secure coding guideline which now reads: "Do not display or evaluate URL parameters using the Spring Expression Language (SpEL)."
The overall impact of this issue is High, for the following reasons: - An attacker could modify and invoke functionality on the application server. - Unauthorized access to data and functionality, as well as account hijacking and remote code execution. - Confidentiality, and Integrity concerns from a successful attack.
https://www.owasp.org/index.php/Expression_Language_Injection
Last week I was researching vulnerabilities in Java Spring to bring our secure coding guidelines up to date. I was going through the existing challenges on our platform and noticed a few on XSS through displaying url parameters in JSP pages. The incorrect code example would look something similar to the following:
<input type="text" name="username" value="${param.username}">
The correct solution was removing the URL parameter altogether and the description mentions that escaping the URL parameter the correct way is also safe.
Now, my job is to formulate the secure coding guideline in a way that is clear to developers and restricts them as little as possible while still writing secure code. In this case, I would prefer to let developers keep their intended functionality and recommend them to do it securely by escaping the URL parameter. This way, the code no longer contains a XSS vulnerability. The above example can be secured like this:
<input type="text" name="username" value="${fn:escapeXml(param.username)}">
And this was our secure coding guideline for a few days, until I stumbled on an OWASP page on expression language injection. This page describes how the Spring Expression Language (SpEL) can be abused for injection with some serious impact, including remote code execution. It was up to me to figure out if there could be cases where code adhering to our secure coding guideline can still be affected by this vulnerability. So I wrote a quick test application to evaluate SpEL expressions, and tested input with and without Xml escaping to see if I could find some scenarios that would not be caught. And I did, there are malicious expressions that do not contain any characters caught by XmlEscape. I published the working demo on our github, which you can find here.
And of course I updated our secure coding guideline which now reads: "Do not display or evaluate URL parameters using the Spring Expression Language (SpEL)."
The overall impact of this issue is High, for the following reasons: - An attacker could modify and invoke functionality on the application server. - Unauthorized access to data and functionality, as well as account hijacking and remote code execution. - Confidentiality, and Integrity concerns from a successful attack.
https://www.owasp.org/index.php/Expression_Language_Injection
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Secure Code Warrior is here for your organization to help you secure code across the entire software development lifecycle and create a culture in which cybersecurity is top of mind. Whether you’re an AppSec Manager, Developer, CISO, or anyone involved in security, we can help your organization reduce risks associated with insecure code.
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Application Security Researcher - R&D Engineer - PhD Candidate
Last week I was researching vulnerabilities in Java Spring to bring our secure coding guidelines up to date. I was going through the existing challenges on our platform and noticed a few on XSS through displaying url parameters in JSP pages. The incorrect code example would look something similar to the following:
<input type="text" name="username" value="${param.username}">
The correct solution was removing the URL parameter altogether and the description mentions that escaping the URL parameter the correct way is also safe.
Now, my job is to formulate the secure coding guideline in a way that is clear to developers and restricts them as little as possible while still writing secure code. In this case, I would prefer to let developers keep their intended functionality and recommend them to do it securely by escaping the URL parameter. This way, the code no longer contains a XSS vulnerability. The above example can be secured like this:
<input type="text" name="username" value="${fn:escapeXml(param.username)}">
And this was our secure coding guideline for a few days, until I stumbled on an OWASP page on expression language injection. This page describes how the Spring Expression Language (SpEL) can be abused for injection with some serious impact, including remote code execution. It was up to me to figure out if there could be cases where code adhering to our secure coding guideline can still be affected by this vulnerability. So I wrote a quick test application to evaluate SpEL expressions, and tested input with and without Xml escaping to see if I could find some scenarios that would not be caught. And I did, there are malicious expressions that do not contain any characters caught by XmlEscape. I published the working demo on our github, which you can find here.
And of course I updated our secure coding guideline which now reads: "Do not display or evaluate URL parameters using the Spring Expression Language (SpEL)."
The overall impact of this issue is High, for the following reasons: - An attacker could modify and invoke functionality on the application server. - Unauthorized access to data and functionality, as well as account hijacking and remote code execution. - Confidentiality, and Integrity concerns from a successful attack.
https://www.owasp.org/index.php/Expression_Language_Injection
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Application Security Researcher - R&D Engineer - PhD Candidate
Secure Code Warrior is here for your organization to help you secure code across the entire software development lifecycle and create a culture in which cybersecurity is top of mind. Whether you’re an AppSec Manager, Developer, CISO, or anyone involved in security, we can help your organization reduce risks associated with insecure code.
Book a demoDownloadResources to get you started
Secure Code Warrior corporate overview
Secure Code Warrior is an AI Software Governance platform designed to enable organizations to safely adopt AI-driven development by bridging the gap between development velocity and enterprise security. The platform addresses the "Visibility Gap," where security teams often lack insights into shadow AI coding tools and the origins of production code.
Secure code training topics & content
Our industry-leading content is always evolving to fit the ever changing software development landscape with your role in mind. Topics covering everything from AI to XQuery Injection, offered for a variety of roles from Architects and Engineers to Product Managers and QA. Get a sneak peek of what our content catalog has to offer by topic and role.
Cyber Resilience Act (CRA) Aligned Learning Pathways
SCW supports Cyber Resilience Act (CRA) readiness with CRA-aligned Quests and conceptual learning collections that help development teams build the Secure by Design, SDLC, and secure coding skills aligned with the CRA’s secure development principles.
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Observe and Secure the ADLC: A Four-Point Framework for CISOs and Development Teams Using AI
While development teams look to make the most of GenAI’s undeniable benefits, we’d like to propose a four-point foundational framework that will allow security leaders to deploy AI coding tools and agents with a higher, more relevant standard of security best practices. It details exactly what enterprises can do to ensure safe, secure code development right now, and as agentic AI becomes an even bigger factor in the future.
