{"id":"CVE-2026-51884","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-51884","generatedAt":"2026-10-28T03:42:12.026Z","title":"The /knowledge_base/upload_temp_docs temporary document upload endpoint in Langchain Chatchat 0.3.1 is vulnerable to path traversal.","description":"The /knowledge_base/upload_temp_docs temporary document upload endpoint in Langchain Chatchat 0.3.1 is vulnerable to path traversal. By crafting malicious filenames, an attacker can write files to arbitrary locations on the server, bypassing the intended restrictions on the temporary directory.","published":"2026-10-01T22:17:03.000Z","lastModified":"2026-10-05T19:17:22.000Z","status":"Deferred","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-22"],"affected":[],"epss":{"score":0.00621,"percentile":0.49576,"date":"2026-10-27","history":[{"date":"2026-10-02","score":0.00154,"percentile":0.03862}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.62%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"scored","label":"Newly scored","at":"2026-10-05T21:15:06.000Z","detail":{"from":null,"score":"9.8","severity":"CRITICAL","fromSeverity":null},"summary":"Now scored CVSS 9.8 CRITICAL."},{"kind":"new","label":"New CVE","at":"2026-10-01T22:17:03.000Z","detail":{"score":null,"severity":null,"publishedAt":"2026-10-01T22:17:03.257Z"},"summary":"New CVE, critical severity (CVSS 9.8)."}],"references":[{"url":"https://gist.github.com/Ro1ME/da028c9ce13dd888e265b9bef01d6eca","source":"cve@mitre.org"},{"url":"https://github.com/chatchat-space/Langchain-Chatchat/issues/5466","source":"cve@mitre.org"},{"url":"https://github.com/chatchat-space/Langchain-Chatchat/issues/5466","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-51884","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}