CVE-2026-116816
llama.cpp b5899 before b10261 Heap Out-of-Bounds Write via plamo2 Tokenizer
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.5
llama.cpp b5899 before b10261 Heap Out-of-Bounds Write via plamo2 Tokenizer
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.
- Record
CVE-2026-116816- CVSS 4.0
- 8.5 High
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 - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-129
- Updated
- 2026-11-02
EUVDEUVD-2026-110569
8.5
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.
- Record
EUVD-2026-110569- CVSS 4.0
- 8.5 High
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-3r8c-j789-2864
8.5
llama.cpp b5899 before b10261 contains a heap out-of-bounds write vulnerability in...
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.
- Record
GHSA-3r8c-j789-2864- CVSS 4.0
- 8.5 High
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 - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-129
- Updated
- 2026-11-02
NVD
8.5
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.
- Record
CVE-2026-116816- CVSS 4.0
- 8.5 High
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 - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-129
- Updated
- 2026-11-02
OSV
8.5
llama.cpp b5899 before b10261 Heap Out-of-Bounds Write via plamo2 Tokenizer
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.
- Record
CVE-2026-116816- CVSS 4.0
- 8.5 High
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 - Weakness
- CWE-129
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-116816
8.5
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.
- Record
DEBIAN-CVE-2026-116816- CVSS 4.0
- 8.5 High
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 - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-116816
8.5
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.
- Record
UBUNTU-CVE-2026-116816- CVSS 4.0
- 8.5 High
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 - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
llama.cppDebian:14 |
before 10271+dfsg-1, plus listed versions 10108+dfsg-110108+dfsg1-110108+dfsg1-210192+dfsg-110192+dfsg-2 Show 44 moreShow less10192+dfsg-2~exp15151+dfsg-1~exp25151+dfsg-1~exp35318+dfsg-15318+dfsg-25713+dfsg-15760+dfsg-15760+dfsg-25760+dfsg-35760+dfsg-45882+dfsg-15882+dfsg-25882+dfsg-35882+dfsg-3~exp15882+dfsg-3~exp25882+dfsg-3~exp35882+dfsg-46641+dfsg-16641+dfsg-26641+dfsg-37593+dfsg-17593+dfsg-27593+dfsg-37965+dfsg-18064+dfsg-18064+dfsg-28461+dfsg-18611+dfsg-18681+dfsg-18870+dfsg-18941+dfsg-19009+dfsg-19071+dfsg-19190+dfsg-19413+dfsg-19555+dfsg-19601+dfsg-19721+dfsg-19895+dfsg-19895+dfsg-29895+dfsg-39951+dfsg-19951+dfsg-29951+dfsg-3 |
10271+dfsg-1 |
llama.cppUbuntu:26.10 |
All versions, plus listed versions 8681+dfsg-19721+dfsg-1ubuntu110438+dfsg-110438+dfsg-1ubuntu1 |
None known |
llama.cppUbuntu:26.04:LTS |
All versions, plus listed versions 5882+dfsg-28064+dfsg-1ubuntu18681+dfsg-1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-116816 is a high vulnerability (CVSS 8.5) in Ggml-org Llama.cpp, published October 27, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.14%, the 2nd percentile. Fixed in llama.cpp 10271+dfsg-1.
References
github.com/ggml-org/llama.cpp/pull/25969
github.com/ggml-org/llama.cpp/pull/26511
github.com/ggml-org/llama.cpp/commit/cf06ad7dfe79e7bf2934150d4fefe1ce8db05490
github.com/ggml-org/llama.cpp/blob/b10259/src/llama-vocab.cpp
github.com/ggml-org/llama.cpp/releases/tag/b10261
vulncheck.com/advisories/llama-cpp-b5899-before-b10261-heap-out-of-bounds-write-via-plamo2-tokenizer
Show 8 moreShow less
nvd.nist.gov/vuln/detail/CVE-2026-116816
github.com/advisories/GHSA-3r8c-j789-2864
github.com/CVEProject/cvelistV5/tree/main/cves/2026/116xxx/CVE-2026-116816.json
security-tracker.debian.org/tracker/CVE-2026-116816
ubuntu.com/security/CVE-2026-116816
cve.org/CVERecord?id=CVE-2026-116816
github.com/cveproject/cvelistv5/tree/main/cves/2026/116xxx/cve-2026-116816.json
nvd.nist.gov/vuln/detail/cve-2026-116816