Auth bypass in Langchat
CVE-2026-111704
LangChat through commit 2a6285a contains a missing authentication vulnerability that allows unauthenticated remote attackers to access REST controllers because no Sa-Token interceptor is registered. Attackers can query /api/v1/auth/users to read plaintext passwords, retrieve LLM provider API keys, create super-admin accounts, and modify or delete data.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@hieuPenguinnn/langchat-missing-global-auth-credential-exposure (third-party-advisory)
- github.com/LangChat/langchat/blob/2a6285a6b8c51d51cdc599771bb667a30bc03f5c/lang… (technical-description)
- github.com/LangChat/langchat/blob/2a6285a6b8c51d51cdc599771bb667a30bc03f5c/lang… (technical-description)
- github.com/LangChat/langchat/blob/2a6285a6b8c51d51cdc599771bb667a30bc03f5c/lang… (technical-description)
- www.vulncheck.com/advisories/langchat-through-commit-2a6285a-missing-authentica… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-111704?
- CVE-2026-111704 is a critical-severity vulnerability in Langchat, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-10-16.
- How severe is CVE-2026-111704?
- Critical severity. CVSS v3 base score is 9.8 out of 10.