Executive brief
Samsung's Keymaster trustlet—a security component that manages cryptographic keys on mobile devices—contains an out-of-bounds write vulnerability. A local attacker with elevated privileges can exploit this to write data beyond intended memory boundaries, potentially compromising the device's security architecture and allowing further system compromise.
Technical details
The vulnerability is an out-of-bounds write in Samsung's Keymaster trustlet (a trusted execution environment component responsible for cryptographic key operations). The flaw allows a local attacker with elevated privileges to write beyond allocated memory boundaries. The attack requires local privileged access—not network-reachable. Successful exploitation can corrupt trustlet memory, bypass security mechanisms, or escalate privileges. Samsung patched this issue in the September 2026 SMR (Security Maintenance Release) Release 1.
Affected products
- Samsung Keymaster trustlet prior to SMR Sep-2026 Release 1
Timeline
- 2026-09-09: disclosed
- 2026-09: patched: Fixed in SMR Sep-2026 Release 1