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CVE

CWE

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CVE-2026-2069

Published: Feb 6, 2026

Modified: Feb 23, 2026

PUBLISHED

CVSS v3.1

3.3

LOW

Description

A flaw has been found in ggml-org llama.cpp up to 55abc39. Impacted is the function llama_grammar_advance_stack of the file llama.cpp/src/llama-grammar.cpp of the component GBNF Grammar Handler. This manipulation causes stack-based buffer overflow. The attack needs to be launched locally. The exploit has been published and may be used. Patch name: 18993. To fix this issue, it is recommended to deploy a patch.

Vendor	Product	Versions
ggml-org	llama.cpp	affected `55abc39`

Weaknesses (CWE)

CVSS v3.1 Details

CVSS v3.1 Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

Low

References

VDB-344636 | ggml-org llama.cpp GBNF Grammar llama-grammar.cpp llama_grammar_advance_stack stack-based overflow

vdb-entry

technical-description

VDB-344636 | CTI Indicators (IOB, IOC, IOA)

signature

permissions-required

Submit #745263 | llama.cpp commit 55abc39 Stack-based Buffer Overflow

third-party-advisory

https://github.com/ggml-org/llama.cpp/issues/18988

issue-tracking

https://github.com/ggml-org/llama.cpp/issues/18988#event-4426704865

issue-tracking

https://github.com/user-attachments/files/24761101/poc.zip

exploit

https://github.com/ggml-org/llama.cpp/pull/18993

issue-tracking

patch

https://github.com/ggml-org/llama.cpp/

product

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