Is CVE-2026-58094 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-58094 being exploited in the wild.

How severe is CVE-2026-58094?

High severity, with a CVSS score of 7.8, published 26 August 2026.

Which products and versions are affected?

Freebsd All supported versions; patches released for 15.1-RELEASE-p3, 15.0-RELEASE-p13, 14.4-RELEASE-p9, and corresponding stable branches.

Is there a fix for CVE-2026-58094?

A patch was published on 2026-08-25: Patches applied to stable/15, releng/15.1, releng/15.0, stable/14, and releng/14.4 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-58094 attacked?

It is attacked with local access, in an operating system.

Am I affected by CVE-2026-58094?

Check whether you run Freebsd at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-58094: FreeBSD POSIX shared memory race condition privilege escalation

CVE-2026-58094 · Severity: high · CVSS 7.8 · Published 2026-08-26

FreeBSD's POSIX shared memory module supports large-page shared memory objects for improved performance. A race condition in the configuration of large-page sizes allows an unprivileged local attacker to exploit the timing gap between checking and setting page configuration to achieve local privilege escalation, potentially gaining administrator-level access to the system.

Technologies: Freebsd. Vendors: Freebsd.

Quick answers

Is CVE-2026-58094 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-58094 being exploited in the wild.
How severe is CVE-2026-58094?: High severity, with a CVSS score of 7.8, published 26 August 2026.
Which products and versions are affected?: Freebsd All supported versions; patches released for 15.1-RELEASE-p3, 15.0-RELEASE-p13, 14.4-RELEASE-p9, and corresponding stable branches.
Is there a fix for CVE-2026-58094?: A patch was published on 2026-08-25: Patches applied to stable/15, releng/15.1, releng/15.0, stable/14, and releng/14.4 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-58094 attacked?: It is attacked with local access, in an operating system.
Am I affected by CVE-2026-58094?: Check whether you run Freebsd at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The FIOSSHMLPGCNF ioctl(2) operation configures page size for large-page POSIX shared memory objects created via shm_create_largepage(3). The vulnerability is a time-of-check-time-of-use (TOCTOU) race condition: the handler checks whether a page size was already configured without holding the rangelock, allowing two concurrent callers to both observe an unconfigured state and set conflicting page sizes, leaving the object in an inconsistent state. An unprivileged local user can exploit this race condition to corrupt kernel data structures and escalate privileges. Patches are available and have been applied to all supported FreeBSD branches (14.4, 15.0, and 15.1) as of 2026-08-25.

Affected products

FreeBSD FreeBSD All supported versions; patches released for 15.1-RELEASE-p3, 15.0-RELEASE-p13, 14.4-RELEASE-p9, and corresponding stable branches

Timeline

2026-08-25: disclosed: FreeBSD Security Advisory SA-26:63 published
2026-08-25: patched: Patches applied to stable/15, releng/15.1, releng/15.0, stable/14, and releng/14.4

References

https://security.freebsd.org/advisories/FreeBSD-SA-26:63.posixshm.asc

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