The maintainers of OpenSSH have released OpenSSH 9.2 to address a number of security bugs, including a memory safety vulnerability in the OpenSSH server.

Tracked as CVE-2023-25136, the shortcoming has been classified as a pre-authentication double free vulnerability that was introduced in version 9.1.

Credited with reporting the flaw to OpenSSH in July 2022 is security researcher Mantas Mikulenas.

Double free flaws arise when a vulnerable piece of code calls the free() function – which is used to deallocate memory blocks – twice, leading to memory corruption, which, in turn, could lead to a crash or execution of arbitrary code.

“While the double-free vulnerability in OpenSSH version 9.1 may raise concerns, it is essential to note that exploiting this issue is no simple task,” Abbasi explained.

Users are recommended to update to OpenSSH 9.2 to mitigate potential security threats.