CVE-2026-105756 vllm-project CVE debrief

Who should care

Defenders of vLLM deployments, especially those using LMCache-MP, should assess their exposure and verify the `cache_salt` validation and error handling in their systems. This includes reviewing the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. Affected roles include those responsible for vLLM deployments, especially with LMCache-MP.

Why it matters

Defenders should care about this vulnerability as it allows a single request to cause a denial of service on LMCache-MP deployments due to loose `cache_salt` validation and uncaught downstream `ValueError`. Affected roles include those responsible for vLLM deployments, especially with LMCache-MP. The vulnerability supports denial of service consequences and requires verification of `cache_salt` validation and error handling.

• Denial of service via uncaught `ValueError`
• Potential for service disruption due to unvalidated client input
• Need for verification of `cache_salt` validation and error handling
• Possible exposure in LMCache-MP deployments

Technical summary

The vulnerability lies in vLLM's handling of the `cache_salt` field in client-supplied request models. The field is only validated as a non-empty string, and when used in LMCache-MP deployments, it can cause a `ValueError` due to stricter checks in the LMCache library. This error is not caught, leading to a potential denial of service. The affected versions and the loose `cache_salt` validator's reach require further confirmation from maintainers. Defenders should prioritize verifying the `cache_salt` validation and error handling in vLLM deployments, especially those using LMCache-MP.

Defensive priority

Defenders should prioritize verifying the `cache_salt` validation and error handling in vLLM deployments, especially those using LMCache-MP.

Recommended defensive actions

• Verify the `cache_salt` validation and error handling in vLLM deployments
• Update to version 0.30.0 or later if possible
• Monitor for potential denial of service attacks
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability is confirmed in vLLM versions up to 0.25.1. The affected versions and the loose `cache_salt` validator's reach require further confirmation from maintainers. Evidence limits suggest that the vulnerability affects LMCache-MP deployments. Defenders should verify the `cache_salt` validation and error handling in their systems, especially in environments using LMCache-MP.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.