What is CVE-2017-16653?

CVE-2017-16653 is a medium-severity cross-site request forgery (CSRF) vulnerability in symfony/security-csrf (composer), affecting versions >= 2.7.0, < 2.7.38. It is fixed in 2.7.38, 2.8.31, 3.2.14, 3.3.13. A victim's authenticated browser session is used to submit forged requests to an application that cannot distinguish them from legitimate ones.

How severe is CVE-2017-16653?

CVE-2017-16653 has a CVSS score of 5.9 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which packages are affected by CVE-2017-16653?

symfony/security-csrf (composer) versions >= 2.7.0, = 2.7.0, = 2.7.0, < 2.7.38.

Is there a fix for CVE-2017-16653?

Yes. CVE-2017-16653 is fixed in 2.7.38, 2.8.31, 3.2.14, 3.3.13. Upgrade to this version or later.

Is CVE-2017-16653 exploitable, and should I be worried?

Whether CVE-2017-16653 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2017-16653 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2017-16653 in symfony/security-csrf

Q: How severe is CVE-2017-16653?

CVE-2017-16653 has a CVSS score of 5.9 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Q: Which packages are affected by CVE-2017-16653?

symfony/security-csrf (composer) versions >= 2.7.0, = 2.7.0, = 2.7.0, < 2.7.38.

Q: Is there a fix for CVE-2017-16653?

Yes. CVE-2017-16653 is fixed in 2.7.38, 2.8.31, 3.2.14, 3.3.13. Upgrade to this version or later.

Q: Is CVE-2017-16653 exploitable, and should I be worried?

Whether CVE-2017-16653 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2017-16653 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2017-16653?

Upgrade: symfony/security-csrf to 2.7.38 or later, symfony/security-csrf to 2.8.31 or later, symfony/security-csrf to 3.2.14 or later, symfony/security-csrf to 3.3.13 or later, symfony/security to 2.7.38 or later, symfony/security to 2.8.31 or later, symfony/security to 3.2.14 or later, symfony/security to 3.3.13 or later, symfony/symfony to 2.7.38 or later, symfony/symfony to 2.8.31 or later, symfony/symfony to 3.2.14 or later, symfony/symfony to 3.3.13 or later.

Summary

Symfony CSRF Vulnerability

An issue was discovered in Symfony before 2.7.38, 2.8.31, 3.2.14, 3.3.13, 3.4-BETA5, and 4.0-BETA5. The current implementation of CSRF protection in Symfony (Version >=2) does not use different tokens for HTTP and HTTPS; therefore the token is subject to MITM attacks on HTTP and can then be used in an HTTPS context to do CSRF attacks.

Impact

A victim's authenticated browser session is used to submit forged requests to an application that cannot distinguish them from legitimate ones. Typical impact: state-changing actions performed as the victim without their consent.

CVE-2017-16653 has a CVSS score of 5.9 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.7.38, 2.8.31, 3.2.14, 3.3.13); upgrading removes the vulnerable code path.

Affected versions

symfony/security-csrf (>= 2.7.0, < 2.7.38) symfony/security-csrf (>= 2.8.0, < 2.8.31) symfony/security-csrf (>= 3.0.0, < 3.2.14) symfony/security-csrf (>= 3.3.0, < 3.3.13) symfony/security (>= 2.7.0, < 2.7.38) symfony/security (>= 2.8.0, < 2.8.31) symfony/security (>= 3.0.0, < 3.2.14) symfony/security (>= 3.3.0, < 3.3.13) symfony/symfony (>= 2.7.0, < 2.7.38) symfony/symfony (>= 2.8.0, < 2.8.31) symfony/symfony (>= 3.0.0, < 3.2.14) symfony/symfony (>= 3.3.0, < 3.3.13)

Security releases

symfony/security-csrf → 2.7.38 (composer) symfony/security-csrf → 2.8.31 (composer) symfony/security-csrf → 3.2.14 (composer) symfony/security-csrf → 3.3.13 (composer) symfony/security → 2.7.38 (composer) symfony/security → 2.8.31 (composer) symfony/security → 3.2.14 (composer) symfony/security → 3.3.13 (composer) symfony/symfony → 2.7.38 (composer) symfony/symfony → 2.8.31 (composer) symfony/symfony → 3.2.14 (composer) symfony/symfony → 3.3.13 (composer)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Upgrade the following packages to resolve this vulnerability:

symfony/security-csrf to 2.7.38 or later; symfony/security-csrf to 2.8.31 or later; symfony/security-csrf to 3.2.14 or later; symfony/security-csrf to 3.3.13 or later; symfony/security to 2.7.38 or later; symfony/security to 2.8.31 or later; symfony/security to 3.2.14 or later; symfony/security to 3.3.13 or later; symfony/symfony to 2.7.38 or later; symfony/symfony to 2.8.31 or later; symfony/symfony to 3.2.14 or later; symfony/symfony to 3.3.13 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2017-16653? CVE-2017-16653 is a medium-severity cross-site request forgery (CSRF) vulnerability in symfony/security-csrf (composer), affecting versions >= 2.7.0, < 2.7.38. It is fixed in 2.7.38, 2.8.31, 3.2.14, 3.3.13. A victim's authenticated browser session is used to submit forged requests to an application that cannot distinguish them from legitimate ones.
How severe is CVE-2017-16653? CVE-2017-16653 has a CVSS score of 5.9 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
Which packages are affected by CVE-2017-16653?
- symfony/security-csrf (composer) (versions >= 2.7.0, < 2.7.38)
- symfony/security (composer) (versions >= 2.7.0, < 2.7.38)
- symfony/symfony (composer) (versions >= 2.7.0, < 2.7.38)
Is there a fix for CVE-2017-16653? Yes. CVE-2017-16653 is fixed in 2.7.38, 2.8.31, 3.2.14, 3.3.13. Upgrade to this version or later.
Is CVE-2017-16653 exploitable, and should I be worried? Whether CVE-2017-16653 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2017-16653 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2017-16653?
- Upgrade symfony/security-csrf to 2.7.38 or later
- Upgrade symfony/security-csrf to 2.8.31 or later
- Upgrade symfony/security-csrf to 3.2.14 or later
- Upgrade symfony/security-csrf to 3.3.13 or later
- Upgrade symfony/security to 2.7.38 or later
- Upgrade symfony/security to 2.8.31 or later
- Upgrade symfony/security to 3.2.14 or later
- Upgrade symfony/security to 3.3.13 or later
- Upgrade symfony/symfony to 2.7.38 or later
- Upgrade symfony/symfony to 2.8.31 or later
- Upgrade symfony/symfony to 3.2.14 or later
- Upgrade symfony/symfony to 3.3.13 or later