CVE-2026-93989CWE-129

CVE-2026-93989

Low · published September 20, 2026

CVSS v3.1
3.1
EPSS
0%
Percentile
9.6
In the wild
Unconfirmed
What it is

vLLM through 0.29.0 fails to properly validate bad_words token indices against the model's generation output width in SamplingParams.update_from_tokenizer(). Attackers can supply out-of-bounds token indices that corrupt logits memory of concurrent requests, causing different in-flight HTTP requests to return incorrect tokens.

The record
Technical detail
CVSS v3.1
3.1 · LOW
Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
CVSS v4.0
2.3 · CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
EPSS
0.00202 · 9.6th percentile
Weakness
CWE-129 · Improper Validation of Array Index
Published
2026-09-20T03:17Z
Affected products (1)
ProductVersionsFixed in
vllm/vllm≤ 0.29.0—
References (5)
https://github.com/vllm-project/vllm · [email protected]https://github.com/vllm-project/vllm/blob/98dff2a81d747d1dba01a47f939f48c3526d4206/vllm/sampling_params.py#L694-L753 · [email protected]https://github.com/vllm-project/vllm/blob/98dff2a81d747d1dba01a47f939f48c3526d4206/vllm/v1/worker/gpu/sample/bad_words.py · [email protected]https://github.com/vllm-project/vllm/pull/48824 · [email protected]https://www.vulncheck.com/advisories/vllm-through-0.29.0-cross-request-logits-corruption-via-bad-words · [email protected]
EPSS history
Timeline
  • 21 SEP 03:37Z
    EPSS moved — → 0%
    epss
  • 19 SEP 22:58Z
    vLLM through 0.29.0 Cross-Request Logits Corruption via bad_words
    cvelistv5