{"id":"CVE-2026-71967","title":"OP-TEE OS through 4.10.0, fixed in commit 0aadfc2, contains a null pointer dereference vulnerability in the Widevine pseudo-TA open_session handler that allows Normal World clients to cause a denial of service when CFG_WIDEVINE_PTA is en…","summary":"OP-TEE OS through 4.10.0, fixed in commit 0aadfc2, contains a null pointer dereference vulnerability in the Widevine pseudo-TA open_session handler that allows Normal World clients to cause a denial of service when CFG_WIDEVINE_PTA is en…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-476"],"published":"2026-08-10","updated":"2026-09-16","sourceUpdated":"2026-09-16T20:32:21.400","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-71967","references":[{"url":"https://github.com/OP-TEE/optee_os/commit/0aadfc23407f50e770eb5ddd871fc208f5626833","label":"disclosure@vulncheck.com"},{"url":"https://github.com/OP-TEE/optee_os/pull/7899","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/op-tee-os-null-pointer-dereference-dos-via-widevine-pta-open-session","label":"disclosure@vulncheck.com"}],"tags":["nvd"],"epss":0.00119,"epssPercentile":0.02034,"ingestedAt":"2026-09-16T21:05:36.837Z","slug":"CVE-2026-71967","body":"## Overview\n\nOP-TEE OS through 4.10.0, fixed in commit 0aadfc2, contains a null pointer dereference vulnerability in the Widevine pseudo-TA open_session handler that allows Normal World clients to cause a denial of service when CFG_WIDEVINE_PTA is enabled. Attackers can open a session directly on the Widevine PTA to trigger an unconditional dereference of a NULL calling session pointer via is_user_ta_ctx(), faulting the TEE at S-EL1 and crashing the trusted execution environment.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}