CVE-2026-43629

Description

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 past buffer boundaries, potentially resulting in heap metadata corruption, model weight corruption, or arbitrary code execution via function pointer overwrite.

Weakness classification

• CWE-190: Integer Overflow or Wraparound
• CWE-787: Out-of-bounds Write

Primary references

• disclosure@vulncheck.com — Patch, Third Party Advisory
• disclosure@vulncheck.com — Mitigation, Patch, Third Party Advisory