How severe is CVE-2024-38513?

CVE-2024-38513 has a CVSS score of 10/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2024-38513?

CVE-2024-38513 affects the following packages: github.com/gofiber/fiber (Go), github.com/gofiber/fiber/v2 (Go), github.com/gofiber/fiber/v2/middleware/session (Go). Ecosystems affected: Go.

How do I fix CVE-2024-38513?

Update github.com/gofiber/fiber to 2.52.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-38513 is resolved across your whole dependency graph.

How do I detect CVE-2024-38513 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/gofiber/fiber. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2024-38513 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2024-38513?

O3 pinpoints whether CVE-2024-38513 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2024-38513 actively exploited in the wild?

No public exploit code has been indexed for CVE-2024-38513 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2024-38513?

CVE-2024-38513 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 48th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

When was CVE-2024-38513 published, and has it been updated?

CVE-2024-38513 was published on July 1, 2024 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2024-38513: Fiber Session Middleware Token Injection Vulner…

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk48th percentile+0.35%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

3 pkgs affected

🐹github.com/gofiber/fiber🐹github.com/gofiber/fiber/v2🐹github.com/gofiber/fiber/v2/middleware/session

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Fiber is an Express-inspired web framework written in Go A vulnerability present in versions prior to 2.52.5 is a session middleware issue in GoFiber versions 2 and above. This vulnerability allows users to supply their own session_id value, resulting in the creation of a session with that key. If a website relies on the mere presence of a session for security purposes, this can lead to significant security risks, including unauthorized access and session fixation attacks. All users utilizing GoFiber's session middleware in the affected versions are impacted. The issue has been addressed in version 2.52.5. Users are strongly encouraged to upgrade to version 2.52.5 or higher to mitigate this vulnerability. Users who are unable to upgrade immediately can apply the following workarounds to reduce the risk: Either implement additional validation to ensure session IDs are not supplied by the user and are securely generated by the server, or regularly rotate session IDs and enforce strict session expiration policies.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/gofiber/fiber`	all versions	2.52.5
🐹Go	`github.com/gofiber/fiber/v2`	all versions	2.52.5
🐹Go	`github.com/gofiber/fiber/v2/middleware/session`	all versions	2.52.5

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/gofiber/fiber. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/gofiber/fiber to 2.52.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-38513 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2024-38513 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2024-38513. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Fiber is an Express-inspired web framework written in Go A vulnerability present in versions prior to 2.52.5 is a session middleware issue in GoFiber versions 2 and above. This vulnerability allows users to supply their own session_id value, resulting in the creation of a session with that key. If a website relies on the mere presence of a session for security purposes, this can lead to significant security risks, including unauthorized access and session fixation attacks. All users utilizing GoFiber's session middleware in the affected versions are impacted. The issue has been addressed in ve

O3 Security · Impact-Aware SCA

Is CVE-2024-38513 in your dependencies?

O3 detects CVE-2024-38513 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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CVE-2024-38513