CVE-2026-105752
LowCVSS 3.1Exploitation Probability (EPSS)
Low risk11th percentile - higher than 11% of all known CVEs
Summary
vLLM is an inference and serving engine for large language models. Prior to 0.30.0, Harmony tool continuations submitted through POST /v1/responses requests rebuild the next-turn engine input without preserving the cache_salt value, placing the continuation prefix in the global unsalted cache namespace even when the caller enabled salting. On deployments with prefix caching enabled (default), an authenticated tenant who can reconstruct a victim's low-entropy post-tool history can submit the same continuation and use the cached_tokens_per_turn count to determine whether the prefix was previously processed, defeating tenant isolation.
Risk Assessment
An authenticated tenant can breach cache isolation and gain information about other tenants' prefix processing. This may lead to information leakage and confidentiality breaches in multi-tenant environments.
Recommendation
Update vLLM to version 0.30.0 or later, which fixes this issue. If updating is not possible, consider disabling prefix caching or restricting access to the /v1/responses endpoint.
Other vulnerabilities in vLLM
See all- CVE-2026-109311Medium
vLLM before 0.29.0 passes uploaded audio to the PyAV/FFmpeg av.open() fallback with only a file-size check, exposing FFmpeg's IAMF parser heap overflow. Authenticated remote attackers can repeatedly upload malformed IAMF containers to /v1/audio/transcriptions, corrupting the heap and crashing the API process.
- CVE-2026-48746Critical
Vulnerability in vLLM versions 0.3.0 to 0.22.0 allows bypass of OpenAI API AuthenticationMiddleware. An attacker can use the API without providing the configured VLLM_API_KEY or --api-key.
- CVE-2026-22778Critical
A vulnerability in vLLM from version 0.8.3 to 0.14.0 leaks a heap address when an invalid image is sent to the multimodal endpoint. This leak reduces ASLR effectiveness from 4 billion to about 8 guesses, facilitating further attacks.
- CVE-2026-105922Medium
A security flaw has been discovered in vllm-project vLLM up to 0.31.0, affecting the function get_token_bin_counts_and_mask in the file vllm/model_executor/layers/utils.py of the Penalty Handler component. Manipulation results in denial of service. Remote exploitation is possible, and the exploit has been publicly released.
- CVE-2026-105775Medium
A security vulnerability in vllm-project vLLM up to 0.31.0 causes an out-of-bounds read in the function conv_ssm_forward in the file mamba_mixer2.py, within the Completions Request Handler component. The attack can be carried out remotely, and the exploit has been publicly disclosed.
- CVE-2026-105760Medium
In vLLM before 0.30.0, a caller can use the media_io_kwargs field to select the GLMGA video backend and supply large fps and max_frames values without a strict work ceiling, causing disproportionate CPU and memory consumption.
- CVE-2026-105759Medium
In vLLM before 0.30.0, the Rust frontend's track_http_metrics middleware records the raw HTTP method token as a Prometheus label, allowing an unauthenticated attacker to send unique arbitrary method tokens and cause permanent creation of label sets, increasing memory usage.
- CVE-2026-105758Medium
In vLLM from 0.24.0 to 0.30.0, the Qwen2VLVideoBackend and Qwen3VLVideoBackend classes accept request-level values for max_frames and fps without server-side ceilings, allowing an unauthenticated caller to decode every frame from attacker-controlled video and consume disproportionate memory.
- CVE-2026-105757Medium
In vLLM before 0.30.0, structured-output request failures can escape validation and reach the EngineCore fatal-error path, allowing ordinary constrained-generation requests to terminate the shared engine.
- CVE-2026-105756Medium
In vLLM before 0.30.0, OpenAI-compatible request models accept a non-empty cache_salt value without enforcing character and length restrictions, which can raise an uncaught ValueError during scheduler cache lookup, causing EngineCore to terminate.
Original NVD description (English source)
vLLM is an inference and serving engine for large language models. Prior to 0.30.0, Harmony tool continuations submitted through "POST /v1/responses" requests rebuild the next-turn engine input without preserving the cache_salt value, placing the continuation prefix in the global unsalted cache namespace even when the caller enabled salting. On deployments with prefix caching enabled, which is the default, an authenticated tenant who can reconstruct a victim's low-entropy post-tool history can submit the same continuation and use the cached_tokens_per_turn count to determine whether the prefix was previously processed, defeating the intended tenant isolation of salted prefix caching. This issue is fixed in version 0.30.0.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

