CVE-2026-41523: vLLM Security Check Bypass via assert Statement

# CVE-2026-41523: vLLM Security Check Bypass via assert Statement

https://gcdradar.vercel.app/incidents/cve-2026-41523-vllm-security-check-bypass-via-assert-stateme · AIR-2026-0736 · closed 2026-06-16

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-06-16
- AI role: Attack on AI
- Products: vLLM
- CVE ids: CVE-2026-41523
- CVSS: 7.5

## Summary

An assert-based validation flaw in vLLM allowed unauthenticated attackers to achieve arbitrary code execution by publishing a malicious model when running in Python optimized mode. No active exploitation has been reported.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-06-22: CVE-2026-41523: vLLM is an inference and serving engine for large language models (LLMs). (https://nvd.nist.gov/vuln/detail/CVE-2026-41523)
- 2026-06-16: CVE-2026-41523: vLLM: Security Check Bypass via assert Statement in Activation Function Loading Allows Arbitrary Code Execution (https://github.com/advisories/GHSA-q8gq-377p-jq3r)

## Sources

- 2026-06-16 GitHub Advisory Database: CVE-2026-41523: vLLM: Security Check Bypass via assert Statement in Activation Function Loading Allows Arbitrary Code Execution https://github.com/advisories/GHSA-q8gq-377p-jq3r
- 2026-06-22 NVD: CVE-2026-41523: vLLM is an inference and serving engine for large language models (LLMs). https://nvd.nist.gov/vuln/detail/CVE-2026-41523

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.