CVE-2024-38513 is a critical-severity (CVSS 10) CWE-384 vulnerability in github.com/gofiber/fiber. A fix is available for github.com/gofiber/fiber — see the affected versions and patch details below.
Fiber Session Middleware Token Injection Vulnerability
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-38513.
EPSS Exploitation Probability
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.
How urgent is this, really
CVE-2024-38513 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/gofiber/fiber🐹github.com/gofiber/fiber/v2🐹github.com/gofiber/fiber/v2/middleware/sessionReal-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
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/gofiber/fiber | all versions | 2.52.5go get github.com/gofiber/fiber@v2.52.5 |
| 🐹Go | github.com/gofiber/fiber/v2 | all versions | 2.52.5go get github.com/gofiber/fiber/v2@v2.52.5 |
| 🐹Go | github.com/gofiber/fiber/v2/middleware/session | all versions | 2.52.5go get github.com/gofiber/fiber/v2/middleware/session@v2.52.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/gofiber/fiber, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-38513 can be triaged on real exposure rather than presence alone.
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
Is CVE-2024-38513 in your dependencies?
O3 Security finds CVE-2024-38513 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.