CVE-2026-58094
TOCTOU race in POSIX shared memory large page configuration
Description
The FIOSSHMLPGCNF ioctl(2) operation configures the page size for a largepage shared memory object. This is intended to be used immediately after creating the object, before any memory is allocated for the object. The handler checked whether a page size had already been configured without holding the rangelock. Two concurrent callers could both observe an unconfigured object and set conflicting page sizes, leaving the object in an inconsistent state. An unprivileged local user can exploit this race to escalate privileges.
INFO
Published Date :
Aug. 26, 2026, 5:39 a.m.
Last Modified :
Aug. 26, 2026, 5:39 a.m.
Remotely Exploit :
No
Source :
freebsd
Affected Products
The following products are affected by CVE-2026-58094
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Acquire rangelock before checking page size configuration.
- Ensure lock is held during page size setting.
- Test concurrent access scenarios thoroughly.
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The following list is the news that have been mention
CVE-2026-58094 vulnerability anywhere in the article.