CVE-2024-38513: Session Middleware Token Injection Vulnerability

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 0.7%, percentile 52: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 52% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes github.com/gofiber/fiber (Go) <= 2.52.4, fixed in 2.52.5; github.com/gofiber/fiber/v2 (Go) <= 2.52.4, fixed in 2.52.5; github.com/gofiber/fiber/v2/middleware/session (Go) <= 2.52.4, fixed in 2.52.5. Check your lockfile, including transitive dependencies.

What it is

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 sessionid 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.

From the GitHub advisory

A security vulnerability has been identified in the Fiber session middleware where a user can supply their own sessionid value, leading to the creation of a session with that key.

Impact The identified vulnerability is a session middleware issue in GoFiber versions 2 and above. This vulnerability allows users to supply their own sessionid 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.

Patches The issue has been addressed in the latest patch. Users are strongly encouraged to upgrade to version 2.52.5 or higher to mitigate this vulnerability.

Workarounds Users who are unable to upgrade immediately can apply the following workarounds to reduce the risk:

1. Validate Session IDs: Implement additional validation to ensure session IDs are not supplied by the user and are securely generated by the server. 2. Session Management: Regularly rotate session IDs and enforce strict session expiration policies.

Weakness type: CWE-384.

Product: github.com/gofiber/fiber (Go) · Assigned by: GitHub_M · Published: 2024-07-01

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.69% probability of exploitation activity in the next 30 days; percentile 52.

Timeline

• 2024-07-01 — CVE record published by GitHub_M
• 2024-07-01 — GitHub-reviewed advisory GHSA-98j2-3j3p-fw2v published (critical)
• 2024-08-02 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-98j2-3j3p-fw2v github.com
2. CVE.org record CVE-2024-38513 cve.org
3. NVD entry CVE-2024-38513 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com

Critical Go advisories · Today’s Security Digest