Langfuse is an open source large language model engineering platform.
CVE-2026-41487
Langfuse is an open source large language model engineering platform. From version 3.68.0 to before version 3.167.0, there is a role-based-access control flaw in the LLM connection update flow. An authenticated, low-privileged user of role “member” in a project could request the update of an existing LLM connection to an attacker-controlled baseUrl, causing Langfuse to reuse the stored provider secret and redirect the test request to an attacker-controlled endpoint. This could expose the plaintext provider LLM API key for that connection. The attack is only possible if a user is already part of a project and has “member” scoped access. This issue has been patched in version 3.167.0.
Assessment
- CVSS
- 5.3 (v4.0)
- Severity
- Medium
- EPSS
- 0.18% chance of exploitation in the next 30 days
- Known exploited
- Not listed in CISA KEV
- Exploit availability
- Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
- Published
- 8 May 2026
- Last updated
- 17 June 2026
- Weakness
- CWE-284
- Assigner
- security-advisories@github.com
CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
At the source
References
- https://github.com/langfuse/langfuse/commit/7527bb0d84bc0a3dc24a4b16d22ed2e46e6dddff
- https://github.com/langfuse/langfuse/commit/e12386f9d4368bbfff24a4ad7fd53641091605ff
- https://github.com/langfuse/langfuse/pull/13027
- https://github.com/langfuse/langfuse/pull/13055
- https://github.com/langfuse/langfuse/releases/tag/v3.167.0
- https://github.com/langfuse/langfuse/security/advisories/GHSA-2524-j966-gfgh
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