// For flags

CVE-2025-52566

llama.cpp tokenizer signed vs. unsigned heap overflow

Severity Score

8.6
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Attend
*SSVC
Descriptions

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.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:Attend
Exploitation
Poc
Automatable
No
Tech. Impact
Total
* Organization's Worst-case Scenario
Timeline
  • 2025-06-18 CVE Reserved
  • 2025-06-24 CVE Published
  • 2025-06-24 CVE Updated
  • 2025-06-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer
  • CWE-195: Signed to Unsigned Conversion Error
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Ggml-org
Search vendor "Ggml-org"
Llama.cpp
Search vendor "Ggml-org" for product "Llama.cpp"
*en
Affected