Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2026-41523
vllm-project vllm — vLLM: Security Check Bypass via assert Statement in Activation Function Loading Allows Arbitrary Code Execution
AV AC PR UI S C I A CVSS EPSS %ile KEV
N H N R U H H H 7.5 .0091 58.7 —
AFFECTED
Product Versions Fixed
vllm < 0.22.0 – —
TIMELINE
Apr 20 Reserved by GitHub_M
Jun 22 EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added.
Jun 22 Published (CNA: GitHub_M)
Aug 21 EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added.
Aug 25 EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added.
Sep 1 EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added.
Sep 2 EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added.
Sep 3 EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added.
Sep 4 EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added.
Description
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.
Lifecycle
Complete event history — 9 events, chronological
| Date | Event | Detail |
|---|
| April 20, 2026 | Reserved | Reserved by GitHub_M |
| June 22, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added. |
| June 22, 2026 | Published | Published (CNA: GitHub_M) |
| August 21, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added. |
| August 25, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added. |
| September 1, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added. |
| September 2, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added. |
| September 3, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added. |
| September 4, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-41523 (vllm-project vllm). Public exploit reference added. |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| vllm-project | vllm | — | < 0.22.0 | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-41523 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
