CVE-2026-34159
llama.cpp: Unauthenticated RCE via GRAPH_COMPUTE buffer=0 bypass in llama.cpp RPC backend
llama.cpp is an inference of several LLM models in C/C++. Prior to version b8492, the RPC backend's deserialize_tensor() skips all bounds validation when a tensor's buffer field is 0. An unauthenticated attacker can read and write arbitrary process memory via crafted GRAPH_COMPUTE messages. Combined with pointer leaks from ALLOC_BUFFER/BUFFER_GET_BASE, this gives full ASLR bypass and remote code execution. No authentication required, just TCP access to the RPC server port. This issue has been patched in version b8492.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
9.8
llama.cpp: Unauthenticated RCE via GRAPH_COMPUTE buffer=0 bypass in llama.cpp RPC backend
llama.cpp is an inference of several LLM models in C/C++. Prior to version b8492, the RPC backend's deserialize_tensor() skips all bounds validation when a tensor's buffer field is 0. An unauthenticated attacker can read and write arbitrary process memory via crafted GRAPH_COMPUTE messages. Combined with pointer leaks from ALLOC_BUFFER/BUFFER_GET_BASE, this gives full ASLR bypass and remote code execution. No authentication required, just TCP access to the RPC server port. This issue has been patched in version b8492.
- Record
CVE-2026-34159- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-119
- Updated
- 2026-11-02
EUVDEUVD-2026-17975
9.8
llama.cpp is an inference of several LLM models in C/C++. Prior to version b8492, the RPC backend's deserialize_tensor() skips all bounds validation when a tensor's buffer field is 0. An unauthenticated attacker can read and write arbitrary process memory via crafted GRAPH_COMPUTE messages. Combined with pointer leaks from ALLOC_BUFFER/BUFFER_GET_BASE, this gives full ASLR bypass and remote code execution. No authentication required, just TCP access to the RPC server port. This issue has been patched in version b8492.
- Record
EUVD-2026-17975- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
NVD
9.8
llama.cpp is an inference of several LLM models in C/C++. Prior to version b8492, the RPC backend's deserialize_tensor() skips all bounds validation when a tensor's buffer field is 0. An unauthenticated attacker can read and write arbitrary process memory via crafted GRAPH_COMPUTE messages. Combined with pointer leaks from ALLOC_BUFFER/BUFFER_GET_BASE, this gives full ASLR bypass and remote code execution. No authentication required, just TCP access to the RPC server port. This issue has been patched in version b8492.
- Record
CVE-2026-34159- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-119
- Updated
- 2026-11-02
OSV
9.8
llama.cpp: Unauthenticated RCE via GRAPH_COMPUTE buffer=0 bypass in llama.cpp RPC backend
llama.cpp is an inference of several LLM models in C/C++. Prior to version b8492, the RPC backend's deserialize_tensor() skips all bounds validation when a tensor's buffer field is 0. An unauthenticated attacker can read and write arbitrary process memory via crafted GRAPH_COMPUTE messages. Combined with pointer leaks from ALLOC_BUFFER/BUFFER_GET_BASE, this gives full ASLR bypass and remote code execution. No authentication required, just TCP access to the RPC server port. This issue has been patched in version b8492.
- Record
CVE-2026-34159- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-119
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-34159
9.8
llama.cpp is an inference of several LLM models in C/C++. Prior to version b8492, the RPC backend's deserialize_tensor() skips all bounds validation when a tensor's buffer field is 0. An unauthenticated attacker can read and write arbitrary process memory via crafted GRAPH_COMPUTE messages. Combined with pointer leaks from ALLOC_BUFFER/BUFFER_GET_BASE, this gives full ASLR bypass and remote code execution. No authentication required, just TCP access to the RPC server port. This issue has been patched in version b8492.
- Record
DEBIAN-CVE-2026-34159- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-34159
9.8
llama.cpp is an inference of several LLM models in C/C++. Prior to version b8492, the RPC backend's deserialize_tensor() skips all bounds validation when a tensor's buffer field is 0. An unauthenticated attacker can read and write arbitrary process memory via crafted GRAPH_COMPUTE messages. Combined with pointer leaks from ALLOC_BUFFER/BUFFER_GET_BASE, this gives full ASLR bypass and remote code execution. No authentication required, just TCP access to the RPC server port. This issue has been patched in version b8492.
- Record
UBUNTU-CVE-2026-34159- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
llama.cppDebian:14 |
before 8611+dfsg-1, plus listed versions 5151+dfsg-1~exp25151+dfsg-1~exp35318+dfsg-15318+dfsg-25713+dfsg-1 Show 21 moreShow less5760+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-1 |
8611+dfsg-1 |
llama.cppUbuntu:25.10 |
All versions, plus listed versions 5318+dfsg-15318+dfsg-25713+dfsg-15760+dfsg-15760+dfsg-35760+dfsg-45882+dfsg-2 |
None known |
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | TeamN4C/SG-2026-0021 | 2026-08-27 |
| PoC in GitHub | casp3r0x0/CVE-2026-34159 | 2026-04-23 |
| PoC in GitHub | rohithronanki/CVE-2026-34159-Vulnerability-Research-Analysis-Detection | 2026-05-04 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-34159 is a critical vulnerability (CVSS 9.8) in Ggml Llama.cpp, published April 1, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 1.62%, the 76th percentile. Fixed in llama.cpp 8611+dfsg-1.
References
github.com/ggml-org/llama.cpp/security/advisories/GHSA-j8rj-fmpv-wcxw
github.com/ggml-org/llama.cpp/pull/20908
github.com/ggml-org/llama.cpp/commit/39bf0d3c6a95803e0f41aaba069ffbee26721042
github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34159.json
nvd.nist.gov/vuln/detail/CVE-2026-34159
security-tracker.debian.org/tracker/CVE-2026-34159
ubuntu.com/security/CVE-2026-34159
cve.org/CVERecord?id=CVE-2026-34159