CVE-2025-52566: high-severity vulnerability in ggml-org llama.cpp
llama.cpp tokenizer signed vs. unsigned heap overflow
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.6epss 0.4%
llama.cpp is an inference of several LLM models in C/C++. Prior to version b5721, there is a signed vs. unsigned integer overflow in llama.cpp's tokenizer implementation (llama_vocab::tokenize) (src/llama-vocab.cpp:3036) resulting in unintended behavior in tokens copying size comparison. Allowing heap-overflowing llama.cpp inferencing engine with carefully manipulated text input during tokenization process. This issue has been patched in version b5721.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Affected products
ggml-org · llama.cppRelated CVEs — ggml-org llama.cpp
In the same product, most dangerous first.
CVE-2026-34159CRITICALllama.cpp: Unauthenticated RCE via GRAPH_COMPUTE buffer=0 bypass in llama.cpp RPC backendEPSS 1.6%CVE-2026-78148MEDIUMggml-org llama.cpp ggml-RPC Server ggml-rpc.cpp graph_compute null pointer dereferenceEPSS 0.7%CVE-2026-17501MEDIUMggml-org llama.cpp JSON-Schema-to-GBNF Conversion json-schema-to-grammar.cpp transform recursionEPSS 0.7%CVE-2026-17500MEDIUMggml-org llama.cpp json-schema-to-grammar.cpp _visit_pattern null pointer dereferenceEPSS 0.7%CVE-2026-86317MEDIUMggml-org llama.cpp RPC Server ggml-rpc.cpp deserialize_tensor assertionEPSS 0.7%CVE-2026-43629CRITICALllama.cpp b4882–b9058 Buffer Overflow in KV Cache State RestoreEPSS 0.7%