{"id":"CVE-2026-41523","summary":"vLLM: Security Check Bypass via assert Statement in Activation Function Loading Allows Arbitrary Code Execution","details":"vLLM is an inference and serving engine for large language models (LLMs). Prior to 0.22.0, an assert-based security check in vLLM's activation function loading allows any unauthenticated attacker to achieve arbitrary code execution on the server by publishing a malicious HuggingFace model, when vLLM runs in Python optimized mode (python -O or PYTHONOPTIMIZE=1). This vulnerability is fixed in 0.22.0.","aliases":["GHSA-q8gq-377p-jq3r","PYSEC-2026-2300"],"modified":"2026-08-05T03:32:34.349889474Z","published":"2026-06-22T22:18:14.494Z","database_specific":{"cwe_ids":["CWE-617","CWE-94"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41523.json","unresolved_ranges":[{"extracted_events":[{"fixed":"0.22.0"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"GitHub_M"},"references":[{"type":"WEB","url":"https://huntr.com/bounties/dcb05b04-e625-41e7-adbc-bbae0cc2d64c"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41523.json"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:36005"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:36006"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-41523"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41523.json"},{"type":"ADVISORY","url":"https://github.com/vllm-project/vllm/security/advisories/GHSA-q8gq-377p-jq3r"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-41523"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2491582"},{"type":"FIX","url":"https://github.com/vllm-project/vllm/commit/b3c7ffcab82c2439726f8cb213800f6f38c023d3"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/vllm-project/vllm","events":[{"introduced":"0"},{"fixed":"b3c7ffcab82c2439726f8cb213800f6f38c023d3"}],"database_specific":{"source":"REFERENCES"}}],"versions":["v0.21.1rc0","v0.20.2rc0","v0.20.1rc0","v0.19.2rc0","v0.19.1rc0","v0.18.2rc0","v0.18.1rc0","v0.17.2rc0","v0.18.0rc0","v0.17.1rc0","v0.17.0rc0","v0.16.0rc1","v0.15.2rc0","v0.16.0rc0","v0.15.0rc1","v0.14.0rc1","v0.14.0rc0","v0.13.0rc1","v0.11.1","v0.11.1rc6","v0.11.1rc5","v0.11.1rc4","v0.11.1rc3","v0.11.1rc2","v0.11.1rc1","v0.11.1rc0","v0.11.0rc1","v0.10.2rc2","v0.10.2rc1","v0.10.1rc1","v0.10.0rc2","v0.10.0","v0.10.0rc1","v0.9.2rc1","v0.9.1rc2","v0.9.1","v0.9.1rc1","v0.9.0","v0.8.4","v0.8.3rc1","v0.8.2","v0.8.1","v0.8.0rc2","v0.8.0rc1","v0.7.3","v0.7.2","v0.7.1","v0.7.0","v0.6.6.post1","v0.6.6","v0.6.5","v0.6.4.post1","v0.6.4","v0.6.3.post1","v0.6.3","v0.6.2","v0.6.1.post2","v0.6.1.post1","v0.6.1","v0.6.0","v0.5.5","v0.5.4","v0.5.3.post1","v0.5.3","v0.5.2","v0.5.1","v0.5.0.post1","v0.5.0","v0.4.3","v0.4.2","v0.4.1","v0.4.0.post1","v0.4.0","v0.3.3","v0.3.2","v0.3.1","v0.3.0","v0.2.7","v0.2.6","v0.2.5","v0.2.4","v0.2.3","v0.2.2","v0.2.1","v0.2.0","v0.1.7","v0.1.6","v0.1.5","v0.1.4","v0.1.3","v0.1.2","v0.1.1","v0.1.0","submission"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-41523.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"}]}