Jail filesystem root escape in FreeBSD via file descriptor passing
Key facts
- Attack vector
- Network
- Privileges required
- None
- 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
FreeBSD releases from 15.1-RELEASE before p4, 15.0-RELEASE before p14, 14.5-RELEASE before p1 and 14.4-RELEASE before p10 are affected. SCM_RIGHTS file descriptor passing does not preserve FD_RESOLVE_BENEATH when a descriptor is transferred, so a process can clear the restriction by sending the descriptor to itself over a Unix domain socket. A process in a jail that receives a directory file descriptor from another jail can escape the jail's filesystem root (CWE-281).
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
SCM_RIGHTS file descriptor passing did not preserve FD_RESOLVE_BENEATH when a descriptor was transferred. A process could clear the restriction by sending the descriptor to itself over a Unix domain socket. 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
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| FreeBSD | FreeBSD | 15.1-RELEASE to before p4; 15.0-RELEASE to before p14; 14.5-RELEASE to before p1; 14.4-RELEASE to before p10 | p4, p14, p1, p10 | Patch available | CNA |
- 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
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:freebsd:freebsd:14.4:-:*:*:*:*:*:* | 14.4 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p1:*:*:*:*:*:* | 14.4 p1 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p2:*:*:*:*:*:* | 14.4 p2 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p3:*:*:*:*:*:* | 14.4 p3 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p4:*:*:*:*:*:* | 14.4 p4 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p5:*:*:*:*:*:* | 14.4 p5 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p6:*:*:*:*:*:* | 14.4 p6 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p7:*:*:*:*:*:* | 14.4 p7 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p8:*:*:*:*:*:* | 14.4 p8 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:14.4:p9:*:*:*:*:*:* | 14.4 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: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
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:freebsd:freebsd:14.5:-:*:*:*:*:*:* | 14.5 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:* | 15.0 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:* | 15.0 p1 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p10:*:*:*:*:*:* | 15.0 p10 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p11:*:*:*:*:*:* | 15.0 p11 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p12:*:*:*:*:*:* | 15.0 p12 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p13:*:*:*:*:*:* | 15.0 p13 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:* | 15.0 p2 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:* | 15.0 p3 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:* | 15.0 p4 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p5:*:*:*:*:*:* | 15.0 p5 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p6:*:*:*:*:*:* | 15.0 p6 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p7:*:*:*:*:*:* | 15.0 p7 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p8:*:*:*:*:*:* | 15.0 p8 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.0:p9:*:*:*:*:*:* | 15.0 p9 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.1:-:*:*:*:*:*:* | 15.1 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.1:p1:*:*:*:*:*:* | 15.1 p1 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.1:p2:*:*:*:*:*:* | 15.1 p2 | Vulnerable | FreeBSD |
| cpe:2.3:o:freebsd:freebsd:15.1:p3:*:*:*:*:*:* | 15.1 p3 | Vulnerable | FreeBSD |
- 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
Upgrade FreeBSD to 15.1-RELEASE p4, 15.0-RELEASE p14, 14.5-RELEASE p1 or 14.4-RELEASE 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-2026-74627 Multiple jail filesystem root escapesPriority MEDIUM 40
- TI-2026-74626 Jail filesystem root escapes in FreeBSD fdescfsPriority LOW 32
Timeline
- 2026-10-15 Threatist record created from CVE-2026-101306
- 2026-10-16 Alias added: GHSA-3c4j-rmc7-2x5m
- 2026-10-16 CVSS score added · CISA ADP
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-16 Priority changed: LOW → MEDIUM
References
More Freebsd vulnerabilities
- 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
Sources
- CVE-2026-101306 · CVE Program
- CVE-2026-101306 · NVD
- FIRST EPSS
- GHSA-3c4j-rmc7-2x5m · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences