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.
References6
- github.com/ggml-org/llama.cpp/blob/b10259/src/llama-vocab.cpp#L…
- github.com/ggml-org/llama.cpp/commit/cf06ad7dfe79e7bf2934150d4f…
- github.com/ggml-org/llama.cpp/pull/25969
- github.com/ggml-org/llama.cpp/pull/26511
- github.com/ggml-org/llama.cpp/releases/tag/b10261
- www.vulncheck.com/advisories/llama-cpp-b5899-before-b10261-heap…
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 4.0
-
8.5
HIGH
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 3 · as of 8 November 2026
- CWE
- CWE-129
Could this be exploited in your environment?
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