Summary
github.com/gorilla/csrf improperly validates TrustedOrigins allowing CSRF attacks
Hosts listed in TrustedOrigins implicitly allow requests from the corresponding HTTP origins, allowing network MitMs to perform CSRF attacks.
After the CVE-2025-24358 fix, a network attacker that places a form at http://example.com can't get it to submit to https://example.com because the Origin header is checked with sameOrigin against a synthetic URL.
However, if a host is added to TrustedOrigins, both its HTTP and HTTPS origins will be allowed, because the schema of the synthetic URL is ignored and only the host is checked. For example, if an application is hosted on https://example.com and adds example.net to TrustedOrigins, a network attacker can serve a form at http://example.net to perform the attack.
Applications should migrate to net/http.CrossOriginProtection, introduced in Go 1.25. If that is not an option, a backport is available as a module at filippo.io/csrf, and a drop-in replacement for the github.com/gorilla/csrf API is available at filippo.io/csrf/gorilla.
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.
Affected versions
Security releases
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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In the interim: Use per-session CSRF tokens on all state-changing operations and verify them server-side. SameSite cookie attributes provide additional defense.
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2025-47909? CVE-2025-47909 is a medium-severity cross-site request forgery (CSRF) vulnerability in github.com/gorilla/csrf (go), affecting versions <= 1.7.3. No fixed version is listed yet. A victim's authenticated browser session is used to submit forged requests to an application that cannot distinguish them from legitimate ones.
- Which versions of github.com/gorilla/csrf are affected by CVE-2025-47909? github.com/gorilla/csrf (go) versions <= 1.7.3 is affected.
- Is there a fix for CVE-2025-47909? No fixed version is listed for CVE-2025-47909 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-47909 exploitable, and should I be worried? Whether CVE-2025-47909 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-2025-47909 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-2025-47909? No fixed version is listed yet. In the interim: Use per-session CSRF tokens on all state-changing operations and verify them server-side. SameSite cookie attributes provide additional defense.