CVE-2025-15576 — Jail chroot escape via fd exchange with a different jail
If two sibling jails are restricted to separate filesystem trees, which is to say that neither of the two jail root directories is an ancestor of the other, jailed processes may nonetheless be able to access a shared directory via a nullfs mount, if the administrator has configured one. In this case, cooperating processes in the two jails may establish a connection using a unix domain socket and exchange directory descriptors with each other. When performing a filesystem name lookup, at each step of the lookup, the kernel checks whether the lookup would descend below the jail root of the current process. If the jail root directory is not encountered, the lookup continues. In a configuration where processes in two different jails are able to exchange file descriptors using a unix domain socket, it is possible for a jailed process to receive a directory for a descriptor that is below that process' jail root. This enables full filesystem access for a jailed process, breaking the chroot. Note that the system administrator is still responsible for ensuring that an unprivileged user on the jail host is not able to pass directory descriptors to a jailed process, even in a patched kernel.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.1% (30-day exploitation probability)+0
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Freebsd Freebsd).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes matching the vulnerability class (privilege escalation), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Freebsd | Freebsd |
version 14.3version 14.3-p8version 14.3-p7version 14.3-p6version 14.3-p5version 14.3-p4version 14.3-p3version 14.3-p2 and 11 moreversion 14.3-p1version 13.5version 13.5-p9version 13.5-p8version 13.5-p7version 13.5-p6version 13.5-p5version 13.5-p4version 13.5-p3version 13.5-p2version 13.5-p1 |
Vulnerable | NIST National Vulnerability Database |
| Freebsd | Freebsd | ≥ 13.5-RELEASE and < p10≥ 14.3-RELEASE and < p9 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.5 | CVSS 3.1 | High | 1.1 | 5.8 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.5 | CVSS 3.1 | High | 1.1 | 5.8 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database |
| 7.5 | CVSS 3.1 | High | — | — | CISA-ADP via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.11%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · freebsd/freebsd
- SSVC assessment updated
- Record published
- CVSS changed · 7.5
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
1 on the record
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-101310 Multiple vulnerabilities in bhyve device models 15h
- High CVE-2026-101311 Multiple vulnerabilities in bhyve device models 15h
- High CVE-2026-101309 Multiple vulnerabilities in bhyve device models 15h
- Unknown CVE-2026-58100 Memory safety bugs in kqueue copy-on-fork implementation 16h
- Unknown CVE-2026-58099 Memory safety bugs in kqueue copy-on-fork implementation 16h
- Unknown CVE-2026-58098 Heap out-of-bounds access in semop(2) 16h
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2025-15576 is "Jail chroot escape via fd exchange with a different jail", rated High. It affects Freebsd (Freebsd); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 0.11% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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