CVE-2026-101305
renameat(2) did not enforce FD_RESOLVE_BENEATH on its directory arguments
- Risk score
- 60/100
- CVSS
- 8.8 v3.1
- Exploit chance (30 days)
- 0.4%
- Published
- 15 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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 …
- Affected
- Freebsd
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Story map
At a glance
Freebsd: Amber, patch this week. 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 …
The flaws
- CVE-2026-101305: Renameat(2) did not enforce FD_RESOLVE_BENEATH on its directory arguments (CVSS 8.8 · EPSS 0%)
- CVE-2026-101306: SCM_RIGHTS file descriptor passing did not preserve FD_RESOLVE_BENEATH when a descriptor was… (CVSS 9.8 · EPSS 0%)
- CVE-2026-101307: Heap buffer overflow (CVSS 9.1 · EPSS 0%)
- CVE-2026-101303: The IPv6 UDP send path for unconnected sockets did not apply the jail policy of rewriting a… (CVSS 7.5 · EPSS 0%)
The fix
Fix: Apply the vendor's security update; see the linked advisory.
Who is exposed: Freebsd
Where it stands
- No known exploitation
Connects to
- Same weakness: CWE-273 (CWE-273). 3 other warnings in 30 days
- Same product: Earlier Freebsd warnings. 6 in the last 90 days
Why it is Yellow
- CVSS 8.8 high
References
Original description
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.
Last activity 15 Oct 2026. Patch Forecast updates every hour.