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TI-2026-41843 Aliases CVE-2026-58093

Kernel use-after-free via tty ioctls

Priority LOW 31CWE-362Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00096 0th percentileScored 2026-11-07
Fix Fixed FreeBSD (FreeBSD): p3, p13, p9

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
FreeBSDFreeBSD15.1-RELEASE to before p3; 15.0-RELEASE to before p13; 14.4-RELEASE to before p9p3, p13, p9Patch availableCNA
  • FreeBSD VendorFreeBSD Affected 15.1-RELEASE to before p3; 15.0-RELEASE to before p13; 14.4-RELEASE to before p9 Fixed in p3, p13, p9 Patch available CNA

CPE configurations NVD · 22

CPEVersionsRoleVendor
cpe:2.3:o:freebsd:freebsd:14.4:p1:*:*:*:*:*:*14.4 p1VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:p2:*:*:*:*:*:*14.4 p2VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:p3:*:*:*:*:*:*14.4 p3VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:p4:*:*:*:*:*:*14.4 p4VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:p5:*:*:*:*:*:*14.4 p5VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:p6:*:*:*:*:*:*14.4 p6VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:p7:*:*:*:*:*:*14.4 p7VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:p8:*:*:*:*:*:*14.4 p8VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:*15.0 p1VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p10:*:*:*:*:*:*15.0 p10VulnerableFreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p1:*:*:*:*:*:* Versions 14.4 p1 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p2:*:*:*:*:*:* Versions 14.4 p2 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p3:*:*:*:*:*:* Versions 14.4 p3 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p4:*:*:*:*:*:* Versions 14.4 p4 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p5:*:*:*:*:*:* Versions 14.4 p5 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p6:*:*:*:*:*:* Versions 14.4 p6 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p7:*:*:*:*:*:* Versions 14.4 p7 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p8:*:*:*:*:*:* Versions 14.4 p8 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:* Versions 15.0 p1 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p10:*:*:*:*:*:* Versions 15.0 p10 Vulnerable ·FreeBSD
Show 12 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:freebsd:freebsd:15.0:p11:*:*:*:*:*:*15.0 p11VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p12:*:*:*:*:*:*15.0 p12VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:*15.0 p2VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:*15.0 p3VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:*15.0 p4VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p5:*:*:*:*:*:*15.0 p5VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p6:*:*:*:*:*:*15.0 p6VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p7:*:*:*:*:*:*15.0 p7VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p8:*:*:*:*:*:*15.0 p8VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p9:*:*:*:*:*:*15.0 p9VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.1:p1:*:*:*:*:*:*15.1 p1VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.1:p2:*:*:*:*:*:*15.1 p2VulnerableFreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p11:*:*:*:*:*:* Versions 15.0 p11 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p12:*:*:*:*:*:* Versions 15.0 p12 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:* Versions 15.0 p2 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:* Versions 15.0 p3 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:* Versions 15.0 p4 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p5:*:*:*:*:*:* Versions 15.0 p5 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p6:*:*:*:*:*:* Versions 15.0 p6 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p7:*:*:*:*:*:* Versions 15.0 p7 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p8:*:*:*:*:*:* Versions 15.0 p8 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p9:*:*:*:*:*:* Versions 15.0 p9 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.1:p1:*:*:*:*:*:* Versions 15.1 p1 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.1:p2:*:*:*:*:*:* Versions 15.1 p2 Vulnerable ·FreeBSD

Remediation

  • Fix · CNA FreeBSD (FreeBSD) Fixed in p3, p13, p9

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    FreeBSD p13, p3, p9

    4 records Highest priority Priority LOW 4 LOW

    Other records, highest priority first

    • TI-2026-41844 TOCTOU race in POSIX shared memory large page configurationPriority LOW 35
    • TI-2026-41841 Kernel use-after-free via the SNDCTL_DSP_SYNCSTART ioctlPriority LOW 35
    • TI-2026-41839 hwpmc fails to detach PMCs during exec credential transitionsPriority LOW 35
    Show all 4 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-58093

References

Advisory 1

  • TI-2011-04182 Buffer overflow in libtelnet/encrypt.c in telnetd in FreeBSD 7.3 through 9.0, MIT… CVSS 2.0HIGH 10.0
  • TI-2007-03684 Integer overflow in print-bgp.c in the BGP dissector in tcpdump 3.9.6 and earlier allows… CVSS 3.1CRITICAL 9.8
  • TI-2002-00376 Integer overflow in xdr_array function in RPC servers for operating systems that use… CVSS 3.1CRITICAL 9.8
  • TI-2024-05929 Openssh: regresshion - race condition in ssh allows rce/dos CVSS 3.1HIGH 8.1
  • TI-2003-00437 Off-by-one error in the fb_realpath() function, as derived from the realpath function in… CVSS 3.1CRITICAL 9.8
  • TI-2003-00642 The prescan function in Sendmail 8.12.9 allows remote attackers to execute arbitrary code… CVSS 2.0HIGH 10.0
See all 576 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences