CVE-2026-43628 (GCVE-0-2026-43628)

Vulnerability from cvelistv5 – Published: 2026-08-06 15:45 – Updated: 2026-08-06 15:45 X_Open Source
VLAI
Title
llama.cpp b3978–b9058 Integer Underflow via DRY Sampler
Summary
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
Severity
8.5 (High)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
  • CWE-191 - Integer Underflow (Wrap or Wraparound)
  • CWE-125 - Out-of-bounds Read
Assigner
References
Impacted products
Vendor Product Version
ggml-org llama.cpp Affected: b3978 , ≤ b9058 (custom)
Affected: 0.11.0 , ≤ 0.17.1 (semver)
Create a notification for this product.
Date Public
2026-05-06 00:00
Credits
Vladimir Tokarev (@G1ND1L4) - Vulnerability Research Tech Lead, Cyera Ofek Itach (@ofekitach) - Security Research Team Lead, Cyera
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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