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TI-2026-41837 Aliases CVE-2026-58087GHSA-v78v-rxq5-6w38

Heap out-of-bounds access in semctl(2)

Priority LOW 35CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
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-191 and the CVSS impact.

Summary

The GETALL and SETALL commands in semctl(2) recorded the number of semaphores in the target set, dropped the lock protecting the set, allocated a buffer sized for that count, and reacquired the lock. A sequence-number check was used to verify that the set had not been replaced in the interim, but the sequence number wraps after 0x8000 create/destroy cycles. By rapidly destroying and recreating semaphore sets at the same index, another process can cause the sequence number to wrap, allowing a set with a different number of semaphores to pass validation. The subsequent copy then reads or writes past the end of the allocated buffer. An unprivileged local user can trigger out-of-bounds reads and writes on kernel heap memory, potentially leading to privilege escalation.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00165 5th percentileScored 2026-11-07
Fix Fixed FreeBSD (FreeBSD): p2, p12, p8

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 p2; 15.0-RELEASE to before p12; 14.4-RELEASE to before p8p2, p12, p8Patch availableCNA
  • FreeBSD VendorFreeBSD Affected 15.1-RELEASE to before p2; 15.0-RELEASE to before p12; 14.4-RELEASE to before p8 Fixed in p2, p12, p8 Patch available CNA

CPE configurations NVD · 25

CPEVersionsRoleVendor
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: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:rc1:*:*:*:*:*:*14.4 rc1VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:*15.0VulnerableFreeBSD
  • 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: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:rc1:*:*:*:*:*:* Versions 14.4 rc1 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:* Versions 15.0 Vulnerable ·FreeBSD
Show 15 more CPE
CPEVersionsRoleVendor
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:15.0:p11:*:*:*:*:*:*15.0 p11VulnerableFreeBSD
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:-:*:*:*:*:*:*15.1VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.1:p1:*:*:*:*:*:*15.1 p1VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.1:rc2:*:*:*:*:*:*15.1 rc2VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.1:rc3-p1:*:*:*:*:*:*15.1 rc3-p1VulnerableFreeBSD
  • 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
  • cpe:2.3:o:freebsd:freebsd:15.0:p11:*:*:*:*:*:* Versions 15.0 p11 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:-:*:*:*:*:*:* Versions 15.1 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:rc2:*:*:*:*:*:* Versions 15.1 rc2 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.1:rc3-p1:*:*:*:*:*:* Versions 15.1 rc3-p1 Vulnerable ·FreeBSD

Remediation

  • Fix · CNA FreeBSD (FreeBSD) Fixed in p2, p12, p8

Fixed in the same release

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

  • Release ·

    FreeBSD p12, p2, p8

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2026-41835 Missing MAC validation in wg(4) packet decryptionPriority LOW 39
    • TI-2026-41838 Race condition in ELF core dump segment countingPriority LOW 33
    Show all 3 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-58087
  2. 2026-10-03 Alias added: GHSA-v78v-rxq5-6w38

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