Auth bypass in Chatchat-Space Langchain-Chatchat
CVE-2026-75128
Langchain-Chatchat through 0.3.1.3 exposes a POST /tools/call API endpoint that invokes any registered tool by name without authentication, leaving the always-registered shell tool callable. Remote attackers can send a single request naming the shell tool to execute arbitrary OS commands as the server user (root in the shipped Docker image).
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
- github.com/chatchat-space/Langchain-Chatchat/blob/a6a9193b5002061719f0eee62c631… (technical-description)
- www.lasso.security/vulnerability-database/cve-2026-75128 (technical-description, exploit)
- www.vulncheck.com/advisories/langchain-chatchat-through-0.3.1.3-unauthenticated… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-75128?
- CVE-2026-75128 is a critical-severity vulnerability in Chatchat-Space Langchain-Chatchat, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-10-20.
- How severe is CVE-2026-75128?
- Critical severity. CVSS v3 base score is 9.8 out of 10.