CVE-2026-58086 ktrace(2) privilege incorrectly validated in jails
An unprivileged user in a FreeBSD jail can modify or disable ktrace flags of a jailed root user, bypassing intended privilege restrictions.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-58086?
CVE-2026-58086 is a high-severity vulnerability in Freebsd Freebsd, published on 19 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
As an inadvertent side effect of an unrelated code change, PRIV_KTRACE was always denied to a jailed root user. Tracing configured by a jailed root user was therefore not flagged as privileged.
An unprivileged user in a jail that has permission to debug the target process can modify the jailed root user's ktrace(2) flags, or disable tracing outright. A jailed root user therefore cannot reliably trace unprivileged processes.
Weakness: CWE-273
Which versions are affected by CVE-2026-58086?
It affects 1 product.
Products include Freebsd Freebsd.
How do I fix CVE-2026-58086?
No fix has been published for CVE-2026-58086 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-58086 being exploited?
There is no known exploitation of CVE-2026-58086 in the wild and no public exploit code.
Other vulnerabilities in Freebsd Freebsd
Sources
Also known as GHSA-5q67-rff6-c784.