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TI-2026-33058 Aliases CVE-2026-45251GHSA-wp9w-fp98-2cxm

Kernel use-after-free via file descriptor syscalls

Priority LOW 35CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
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

A file descriptor can be closed while a thread is blocked in a poll(2) or select(2) call waiting for that descriptor. Because the blocked thread does not hold a reference to the underlying object, this closure may result in the object being freed while the thread remains blocked. In this situation, the kernel must remove the blocked thread from the per-object wait queue prior to freeing the object. In the case of some file descriptor types, the kernel failed to unlink blocked threads from the object before freeing it. When the blocked thread is subsequently woken, it accesses memory that has already been freed resulting in a use-after-free vulnerability. The use-after-free vulnerability may be triggered by an unprivileged local user and can be exploited to obtain superuser privileges.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0017 6th percentileScored 2026-11-07
Fix Fixed FreeBSD (FreeBSD): p9, p5, p14

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
FreeBSDFreeBSD15.0-RELEASE to before p9; 14.4-RELEASE to before p5; 14.3-RELEASE to before p14p9, p5, p14Patch availableCNA
  • FreeBSD VendorFreeBSD Affected 15.0-RELEASE to before p9; 14.4-RELEASE to before p5; 14.3-RELEASE to before p14 Fixed in p9, p5, p14 Patch available CNA

CPE configurations NVD · 29

CPEVersionsRoleVendor
cpe:2.3:o:freebsd:freebsd:14.3:-:*:*:*:*:*:*14.3VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p1:*:*:*:*:*:*14.3 p1VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p10:*:*:*:*:*:*14.3 p10VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p11:*:*:*:*:*:*14.3 p11VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p12:*:*:*:*:*:*14.3 p12VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p13:*:*:*:*:*:*14.3 p13VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p2:*:*:*:*:*:*14.3 p2VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p3:*:*:*:*:*:*14.3 p3VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p4:*:*:*:*:*:*14.3 p4VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p5:*:*:*:*:*:*14.3 p5VulnerableFreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:-:*:*:*:*:*:* Versions 14.3 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p1:*:*:*:*:*:* Versions 14.3 p1 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p10:*:*:*:*:*:* Versions 14.3 p10 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p11:*:*:*:*:*:* Versions 14.3 p11 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p12:*:*:*:*:*:* Versions 14.3 p12 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p13:*:*:*:*:*:* Versions 14.3 p13 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p2:*:*:*:*:*:* Versions 14.3 p2 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p3:*:*:*:*:*:* Versions 14.3 p3 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p4:*:*:*:*:*:* Versions 14.3 p4 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p5:*:*:*:*:*:* Versions 14.3 p5 Vulnerable ·FreeBSD
Show 19 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:freebsd:freebsd:14.3:p6:*:*:*:*:*:*14.3 p6VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p7:*:*:*:*:*:*14.3 p7VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p8:*:*:*:*:*:*14.3 p8VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.3:p9:*:*:*:*:*:*14.3 p9VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:-:*:*:*:*:*:*14.4VulnerableFreeBSD
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:rc1:*:*:*:*:*:*14.4 rc1VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:*15.0VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:*15.0 p1VulnerableFreeBSD
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:14.3:p6:*:*:*:*:*:* Versions 14.3 p6 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p7:*:*:*:*:*:* Versions 14.3 p7 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p8:*:*:*:*:*:* Versions 14.3 p8 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.3:p9:*:*:*:*:*:* Versions 14.3 p9 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:-:*:*:*:*:*:* Versions 14.4 Vulnerable ·FreeBSD
  • 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:rc1:*:*:*:*:*:* Versions 14.4 rc1 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:* Versions 15.0 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: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

Remediation

  • Fix · CNA FreeBSD (FreeBSD) Fixed in p9, p5, p14

Fixed in the same release

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

  • Release ·

    FreeBSD p14, p5, p9

    7 records Highest priority Priority LOW 7 LOW

    Other records, highest priority first

    • TI-2026-28435 select(2) file descriptor set overflow causes stack overflowPriority LOW 39
    • TI-2026-33060 Missing validation in ptrace(PT_SC_REMOTE)Priority LOW 38
    • TI-2026-33057 Stack buffer overflow via setcred(2)Priority LOW 36
    Show all 7 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-45251
  2. 2026-10-03 Alias added: GHSA-wp9w-fp98-2cxm

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