{"id":"DEBIAN-CVE-2025-56005","details":"An undocumented and unsafe feature in the PLY (Python Lex-Yacc) library 3.11 allows Remote Code Execution (RCE) via the `picklefile` parameter in the `yacc()` function. This parameter accepts a `.pkl` file that is deserialized with `pickle.load()` without validation. Because `pickle` allows execution of embedded code via `__reduce__()`, an attacker can achieve code execution by passing a malicious pickle file. The parameter is not mentioned in official documentation or the GitHub repository, yet it is active in the PyPI version. This introduces a stealthy backdoor and persistence risk. NOTE: A third-party states that this vulnerability should be rejected because the proof of concept does not demonstrate arbitrary code execution and fails to complete successfully.","modified":"2026-02-07T05:17:08.542241Z","published":"2026-01-20T19:15:49.247Z","upstream":["CVE-2025-56005"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-56005"}],"affected":[{"package":{"name":"ply","ecosystem":"Debian:11","purl":"pkg:deb/debian/ply?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.11-10","3.11-4","3.11-5","3.11-6","3.11-7","3.11-8","3.11-9"],"ecosystem_specific":{"urgency":"unimportant"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-56005.json"}},{"package":{"name":"ply","ecosystem":"Debian:12","purl":"pkg:deb/debian/ply?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.11-10","3.11-5","3.11-6","3.11-7","3.11-8","3.11-9"],"ecosystem_specific":{"urgency":"unimportant"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-56005.json"}},{"package":{"name":"ply","ecosystem":"Debian:13","purl":"pkg:deb/debian/ply?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.11-10","3.11-9"],"ecosystem_specific":{"urgency":"unimportant"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-56005.json"}},{"package":{"name":"ply","ecosystem":"Debian:14","purl":"pkg:deb/debian/ply?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.11-10","3.11-9"],"ecosystem_specific":{"urgency":"unimportant"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-56005.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}