High severity · published Oct 27, 2026
CVE-2026-116816
llama.cpp b5899 before b10261 Heap Out-of-Bounds Write via plamo2 Tokenizer
New
7.8
CVSS
0.1%
EPSS
No
On KEV
Description
llama.cpp b5899 before b10261 contains a heap out-of-bounds write vulnerability in llm_tokenizer_plamo2::build that allows attackers to corrupt heap memory via crafted GGUF models. Attackers can supply BYTE-typed token text like <0x-1> whose negative parsed value writes token ids before the bytes_ buffer during model loading, causing crashes or potential code execution.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LL
llama.cpp · ggml-org
b5899 before b10261 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-116816
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-116816
github.com
https://github.com/ggml-org/llama.cpp/blob/b10259/src/llama-vocab.cpp#L1376-L1377
github.com
https://github.com/ggml-org/llama.cpp/commit/cf06ad7dfe79e7bf2934150d4fefe1ce8db05490
github.com
https://github.com/ggml-org/llama.cpp/pull/25969
github.com
https://github.com/ggml-org/llama.cpp/pull/26511
github.com
https://github.com/ggml-org/llama.cpp/releases/tag/b10261
www.vulncheck.com
https://www.vulncheck.com/advisories/llama-cpp-b5899-before-b10261-heap-out-of-bounds-write-via-plamo2-tokenizer
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