CVE-2026-58094 — TOCTOU race in POSIX shared memory large page configuration
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 an…
Published: 2026-08-26 · CVSS: 7.8 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7