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TI-2026-74627 Aliases CVE-2026-101305GHSA-crp4-cfvg-6vr3

Multiple jail filesystem root escapes

Priority MEDIUM 40CWE-273Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

Summary

Several FreeBSD releases contain jail filesystem root escape flaws (CWE-273). renameat(2) does not enforce FD_RESOLVE_BENEATH on its directory arguments, so a jailed process can rename a directory relative to a restricted descriptor and then escape the jail root with fchdir(2) if the directory sits on a filesystem also reachable from the jail root. A process that holds a directory descriptor received from another jail can use the same techniques. CVSS 3.1 rates it 8.8 HIGH, with high confidentiality, integrity and availability impact.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

renameat(2) did not enforce FD_RESOLVE_BENEATH on its directory arguments. A jailed process could rename a directory relative to a restricted descriptor, then escape the jail root via fchdir(2). This requires the directory to reside on a filesystem that is also reachable from the jail's root. A process in a jail that has received a directory file descriptor from another jail can use these techniques to escape the jail's filesystem root restriction.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00232 14th percentileScored 2026-11-07
Fix Fixed FreeBSD (FreeBSD): p4, p14, p1 +1

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 p4; 15.0-RELEASE to before p14; 14.5-RELEASE to before p1; 14.4-RELEASE to before p10p4, p14, p1, p10Patch availableCNA
  • FreeBSD VendorFreeBSD Affected 15.1-RELEASE to before p4; 15.0-RELEASE to before p14; 14.5-RELEASE to before p1; 14.4-RELEASE to before p10 Fixed in p4, p14, p1, p10 Patch available CNA

CPE configurations NVD · 29

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:p8:*:*:*:*:*:*14.4 p8VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:14.4:p9:*:*:*:*:*:*14.4 p9VulnerableFreeBSD
  • 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:p8:*:*:*:*:*:* Versions 14.4 p8 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.4:p9:*:*:*:*:*:* Versions 14.4 p9 Vulnerable ·FreeBSD
Show 19 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:freebsd:freebsd:14.5:-:*:*:*:*:*:*14.5VulnerableFreeBSD
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:p10:*:*:*:*:*:*15.0 p10VulnerableFreeBSD
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:p13:*:*:*:*:*:*15.0 p13VulnerableFreeBSD
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:p2:*:*:*:*:*:*15.1 p2VulnerableFreeBSD
cpe:2.3:o:freebsd:freebsd:15.1:p3:*:*:*:*:*:*15.1 p3VulnerableFreeBSD
  • cpe:2.3:o:freebsd:freebsd:14.5:-:*:*:*:*:*:* Versions 14.5 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: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:p12:*:*:*:*:*:* Versions 15.0 p12 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.0:p13:*:*:*:*:*:* Versions 15.0 p13 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:p2:*:*:*:*:*:* Versions 15.1 p2 Vulnerable ·FreeBSD
  • cpe:2.3:o:freebsd:freebsd:15.1:p3:*:*:*:*:*:* Versions 15.1 p3 Vulnerable ·FreeBSD

Remediation

Update FreeBSD 15.1-RELEASE to p4, FreeBSD 15.0-RELEASE to p14, FreeBSD 14.5-RELEASE to p1 and FreeBSD 14.4-RELEASE to p10.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA FreeBSD (FreeBSD) Fixed in p4, p14, p1, p10

Fixed in the same release

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

  • Advisory ·

    FreeBSD — security.freebsd.org/advisories/FreeBSD-SA-26:66.jail.asc

    3 records Highest priority Priority MEDIUM 2 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-74628 Jail filesystem root escape in FreeBSD via file descriptor passingPriority MEDIUM 48
    • TI-2026-74626 Jail filesystem root escapes in FreeBSD fdescfsPriority LOW 32
    Show all 3 records → Advisory →

Timeline

  1. 2026-10-15 Threatist record created from CVE-2026-101305
  2. 2026-10-16 Alias added: GHSA-crp4-cfvg-6vr3
  3. 2026-10-16 CVSS score added · CISA ADP
  4. 2026-10-16 CISA SSVC decision points changed
  5. 2026-10-18 Priority changed: LOW → MEDIUM

References

Patch 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