CVE-2026-58093

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.

Affected Software

VendorProductVersion RangeStatus
FreeBSDFreeBSD15.1-RELEASE < p3affected
FreeBSDFreeBSD15.0-RELEASE < p13affected
FreeBSDFreeBSD14.4-RELEASE < p9affected

Weaknesses

  • CWE-362: CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
  • CWE-416: CWE-416: Use After Free

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References