Symcrypt
Monthly
Heap buffer overflow in Microsoft SymCrypt versions 103.5.0 through 103.10.x allows local authenticated attackers to cause denial of service or limited integrity compromise via silent truncation of a 64-bit leaf count parameter to 32 bits in the SymCryptXmssSign function during XMSS^MT signature operations with tree height >= 32. Real-world risk is significantly mitigated by the requirement for attacker-controlled signing parameters (uncommon in production), the private-key-operation context, and Microsoft's explicit guidance that XMSS^MT signing should only occur in Hardware Security Modules and is provided in SymCrypt for testing purposes only. No public exploit code or active exploitation has been identified.
Heap buffer overflow in Microsoft SymCrypt versions 103.5.0 through 103.10.x allows local authenticated attackers to cause denial of service or limited integrity compromise via silent truncation of a 64-bit leaf count parameter to 32 bits in the SymCryptXmssSign function during XMSS^MT signature operations with tree height >= 32. Real-world risk is significantly mitigated by the requirement for attacker-controlled signing parameters (uncommon in production), the private-key-operation context, and Microsoft's explicit guidance that XMSS^MT signing should only occur in Hardware Security Modules and is provided in SymCrypt for testing purposes only. No public exploit code or active exploitation has been identified.