CVE-2026-101304
When fdescfs(4) was mounted in a jail with the "nodup" option, opening /dev/fd/N returned a…
- Risk score
- 43/100
- CVSS
- 7.1 v3.1
- Exploit chance (30 days)
- 0.1%
- Published
- 15 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- When fdescfs(4) was mounted in a jail with the "nodup" option, opening /dev/fd/N returned a descriptor that did not inherit FD_RESOLVE_BENEATH or the Capsicum capability rights of descriptor N. A process in a jail that has received a directory file descriptor from another jail can use these techniques to escape the ja…
- Affected
- Freebsd
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 7.1 high
References
Original description
When fdescfs(4) was mounted in a jail with the "nodup" option, opening /dev/fd/N returned a descriptor that did not inherit FD_RESOLVE_BENEATH or the Capsicum capability rights of descriptor N. 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.