PatchTheCEVCVE-2026-43629: llama.cpp builds b4882 through b9058 contain a heap buffer overflow vulnerability in the KV cache state restor
46
This month
HIGH 8.1REMOTEUPGRADE
CVE-2026-43629 is a high-severity flaw (CVSS 8.1) affecting llama.cpp. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
llama.cpp builds b4882 through b9058 contain a heap buffer overflow vulnerability in the KV cache state restore path where the state_read_data() function computes write size without overflow checking, allowing attackers with write access to the slot_save_path directory to corrupt heap memory. Attackers can craft malicious state files where cell_count multiplication overflows or exceeds tensor buffer allocation to write attacker-controlled bytes p
Why this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
ggml llama.cpp UPGRADE
Affected: >= b4882 and <= b9058
Fixed in: newer than b9058
Safe to downgrade to: a release before b4882
1. Check installed version
apt-cache policy llama.cpp || rpm -q llama.cpp || llama.cpp --version
2. UPGRADE to newer than b9058 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade llama.cpp
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade llama.cpp
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before b4882 (Debian / Ubuntu)
apt-cache madison llama.cpp
sudo apt install llama.cpp=<VERSION_BEFORE_b4882>
sudo apt-mark hold llama.cpp
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list llama.cpp
sudo dnf downgrade llama.cpp-<VERSION_BEFORE_b4882>
sudo dnf versionlock add llama.cpp
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
Exact fixes by distribution
Fedora 46 · kwin-zones · FIXED · 1.0.13-1.fc46 · FEDORA-2026-95888f332b · source
sudo dnf upgrade --advisory=FEDORA-2026-95888f332b
Fedora ELN · nginx-mod-brotli · FIXED · 1.0.0~rc-16.eln159 · FEDORA-2026-501a6a8273 · source
sudo dnf upgrade --advisory=FEDORA-2026-501a6a8273
RHEL AI (RHEL AI) 3 · rhelai3/bootc-cuda-rhel9 · NO FIX YET
RHEL AI (RHEL AI) 3 · rhelai3/bootc-gaudi-rhel9 · DEFERRED
RHEL AI (RHEL AI) 3 · rhelai3/bootc-rocm-rhel9 · NO FIX YET
RHEL AI (RHEL AI) 3 · rhelai3/disk-image-cuda-rhel9 · NO FIX YET
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Related CVEs
- CVE-2026-43631 HIGH 8.1 UPGRADE llama.cpp builds b7492 through the latest b9060 contains a use-after-free vulnerability in the vocab pointer o
- CVE-2026-43632 HIGH 8.1 UPGRADE llama.cpp builds b7492 through the latest b9060 contains a use-after-free vulnerability in llama-server affect
- CVE-2026-70640 HIGH 7.0 UPGRADE llama.cpp builds b1886 through b7445 contain a race condition use-after-free vulnerability in the LLaMA-Androi
- CVE-2026-43622 HIGH 7.8 UPGRADE llama.cpp builds b1886 through b7445 contain a double free vulnerability in the LLaMA-Android JNI wrapper wher
- CVE-2026-43628 HIGH 7.8 UPGRADE llama.cpp builds b3978 through b9058 contain an integer underflow and out-of-bounds read vulnerability in the