CVE-2026-58093
HighCVSS 7.0Exploitation Probability (EPSS)
Low risk1th percentile - higher than 1% of all known CVEs
Summary
The TIOCSCTTY ioctl handler drops the tty lock in order to acquire the process tree lock. After reacquiring the tty lock, the handler did not revalidate the state of the terminal, and could proceed to link a terminal that was concurrently being destroyed to the calling process' session. An unprivileged local user can exploit this race condition to escalate privileges.
Risk Assessment
A local unprivileged user can escalate privileges, potentially leading to full system compromise.
Recommendation
Apply the vendor patch that addresses the race condition in the TIOCSCTTY ioctl handler.
Other vulnerabilities in Operating System Kernel
See all- CVE-2026-58094High
The FIOSSHMLPGCNF ioctl(2) operation configures the page size for a largepage shared memory object. The handler checked whether a page size had already been configured without holding the rangelock. Two concurrent callers could both observe an unconfigured object and set conflicting page sizes, leaving the object in an inconsistent state. An unprivileged local user can exploit this race to escalate privileges.
- CVE-2026-58091High
The implementation of this ioctl attempts to acquire locks on all channels in a sync group. If locking a channel would block, it releases the sync group list lock and sleeps. Upon reawakening, it is possible that the sync group structure is freed, but the implementation did not handle this possibility. On a system with multiple audio devices, an unprivileged local user can exploit this use-after-free to escalate privileges.
Original NVD description (English source)
The TIOCSCTTY ioctl handler drops the tty lock in order to acquire the process tree lock. After reacquiring the tty lock, the handler did not revalidate the state of the terminal, and could proceed to link a terminal that was concurrently being destroyed to the calling process' session. An unprivileged local user can exploit this race condition to escalate privileges.