{"id":"CVE-2021-24040","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-24040","generatedAt":"2026-11-05T01:11:08.074Z","title":"Due to use of unsafe YAML deserialization logic, an attacker with the ability to modify local YAML configuration files could provide malicious input, resulting in remote code execution or similar risks.","description":"Due to use of unsafe YAML deserialization logic, an attacker with the ability to modify local YAML configuration files could provide malicious input, resulting in remote code execution or similar risks. This issue affects ParlAI prior to v1.1.0.","published":"2021-09-10T22:15:07.000Z","lastModified":"2026-06-17T03:39:12.000Z","status":"Modified","sourceIdentifier":"cve-assign@fb.com","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-502"],"affected":["facebook/parlai"],"epss":{"score":0.17353,"percentile":0.97119,"date":"2026-11-03","history":[]},"kev":{"listed":false},"exploits":{"count":1,"verified":false,"firstPublished":"2021-09-13","source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[{"edbId":50289,"kind":"exploit","title":"Facebook ParlAI 1.0.0 -  Deserialization of Untrusted Data in parlai","url":"https://www.exploit-db.com/exploits/50289","sourceUrl":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/python/local/50289.py","file":"exploits/python/local/50289.py","published":"2021-09-13","added":"2021-09-13","updated":"2021-09-13","author":"Abhiram V","type":"local","platform":"python","port":null,"verified":false,"codes":["CVE-2021-24040"],"tags":null,"aliases":null,"applicationUrl":null,"screenshotUrl":null,"referenceUrl":null}]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 17.4%, higher than 97% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://packetstormsecurity.com/files/164136/Facebook-ParlAI-1.0.0-Code-Execution-Deserialization.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"cve-assign@fb.com"},{"url":"https://github.com/facebookresearch/ParlAI/releases/tag/v1.1.0","tags":["Release Notes","Third Party Advisory"],"source":"cve-assign@fb.com"},{"url":"https://github.com/facebookresearch/ParlAI/security/advisories/GHSA-m87f-9fvv-2mgg","tags":["Patch","Third Party Advisory"],"source":"cve-assign@fb.com"},{"url":"http://packetstormsecurity.com/files/164136/Facebook-ParlAI-1.0.0-Code-Execution-Deserialization.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/facebookresearch/ParlAI/releases/tag/v1.1.0","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/facebookresearch/ParlAI/security/advisories/GHSA-m87f-9fvv-2mgg","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-24040","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."}