PatchTheCVECVE-2026-70638: llama.cpp builds b1886 through b7445 contain an integer overflow vulnerability in the LLaMA-Android JNI wrappe
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Routine
HIGH 7.8UPGRADE
CVE-2026-70638 is a high-severity flaw (CVSS 7.8) affecting llama.cpp. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
llama.cpp builds b1886 through b7445 contain an integer overflow vulnerability in the LLaMA-Android JNI wrapper where the new_1batch() function multiplies sizeof(llama_seq_id) by an attacker-controlled n_seq_max parameter without overflow validation, causing heap buffer allocation to wrap and allocate insufficient memory. Attackers can exploit this by providing a crafted n_seq_max value through a malicious model file or JNI call to trigger heap c
Why this priority
- High severity
A fixed release or distro patch exists.
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
ggml llama.cpp UPGRADE
Affected: >= b1886 and <= b7445
Fixed in: newer than b7445
Safe to downgrade to: a release before b1886
1. Check installed version
apt-cache policy llama.cpp || rpm -q llama.cpp || llama.cpp --version
2. UPGRADE to newer than b7445 (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 b1886 (Debian / Ubuntu)
apt-cache madison llama.cpp
sudo apt install llama.cpp=<VERSION_BEFORE_b1886>
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_b1886>
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.
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.
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