CVE-2026-43628

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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/Vladimir-tokarev-cyera/llama-cpp-security-patches
https://www.vulncheck.com/advisories/llama-cpp-b3978-b9058-integer-underflow-via-dry-sampler

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-06 22:17

Updated : 2026-08-31 20:31

NVD link : CVE-2026-43628

Mitre link : CVE-2026-43628

CVE.ORG link : CVE-2026-43628

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

CWE-191

Integer Underflow (Wrap or Wraparound)

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