CVE-2026-70640
Severity CVSS v4.0:
HIGH
Type:
CWE-362
Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Publication date:
06/08/2026
Last modified:
07/08/2026
Description
llama.cpp builds b1886 through b7445 contain a race condition use-after-free vulnerability in the LLaMA-Android JNI wrapper where bench_1model() and free_1context() lack synchronization, allowing Thread A to operate on freed memory while Thread B concurrently frees the llama_context. Attackers can exploit this by performing heap spray with attacker-controlled data containing a fake vtable to hijack the vtable pointer at offset +0x30, causing llama_batch_allocr::clear() to dereference arbitrary memory and achieve remote code execution.
Impact
Base Score 4.0
7.30
Severity 4.0
HIGH
Base Score 3.x
7.00
Severity 3.x
HIGH
References to Advisories, Solutions, and Tools
- https://github.com/Vladimir-tokarev-cyera/llama-cpp-security-patches
- https://github.com/ggml-org/llama.cpp/commit/5c0d18881e0e9794c96b2602736b758bac9d9388
- https://github.com/ggml-org/llama.cpp/releases/tag/b7446
- https://www.vulncheck.com/advisories/llama-cpp-b1886-b7445-race-condition-use-after-free-via-llama-android-cpp