CVE-2026-43628
llama.cpp b3978–b9058 Integer Underflow via DRY Sampler
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
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 b3978–b9058 Integer Underflow via DRY Sampler
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
- Record
CVE-2026-43628- 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-191, CWE-125
- Updated
- 2026-11-02
EUVDEUVD-2026-54283
8.5
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
- Record
EUVD-2026-54283- 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-wvf4-v63v-mwm5
8.5
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read...
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
- Record
GHSA-wvf4-v63v-mwm5- 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-125
- Updated
- 2026-11-02
NVD
8.5
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
- Record
CVE-2026-43628- 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-125, CWE-191
- Updated
- 2026-11-02
OSV
8.5
llama.cpp b3978–b9058 Integer Underflow via DRY Sampler
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
- Record
CVE-2026-43628- 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-125, CWE-191
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-43628
8.5
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
- Record
DEBIAN-CVE-2026-43628- 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-2026-43628
8.5
llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the DRY sampler that allows unauthenticated attackers to trigger a heap buffer underflow by sending a crafted HTTP request with dry_allowed_length set to INT32_MIN to the /v1/completions or /v1/chat/completions endpoints. Attackers can exploit this vulnerability to crash the server with SIGSEGV causing denial of service for all connected users, or corrupt token sampling probabilities by reading garbage values from memory before the allocated buffer.
- Record
UBUNTU-CVE-2026-43628- 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 |
All versions, plus listed versions 10108+dfsg-110108+dfsg1-110108+dfsg1-210192+dfsg-110192+dfsg-2 Show 45 moreShow less10192+dfsg-2~exp110271+dfsg-110344+dfsg-110438+dfsg-11:0.1.2+dfsg-1~exp11:0.2.0+dfsg1-11:0.2.0+dfsg1-1~exp11:0.4.0+dfsg-11:0.4.1+dfsg-11:0.5.0+dfsg-11:0.5.0+dfsg-21:0.6.0+dfsg-11:0.6.0+dfsg-21:0.7.0+dfsg-11:0.7.0+dfsg-25151+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-1 |
None known |
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-2026-43628 is a high vulnerability (CVSS 8.5) in Ggml Llama.cpp, published August 6, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.23%, the 14th percentile. No source names a fixed version.
References
github.com/Vladimir-tokarev-cyera/llama-cpp-security-patches
vulncheck.com/advisories/llama-cpp-b3978-b9058-integer-underflow-via-dry-sampler
nvd.nist.gov/vuln/detail/CVE-2026-43628
github.com/advisories/GHSA-wvf4-v63v-mwm5
github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43628.json
security-tracker.debian.org/tracker/CVE-2026-43628
ubuntu.com/security/CVE-2026-43628
cve.org/CVERecord?id=CVE-2026-43628
Left out here: 13 versions. The JSON record has them.