CVE-2026-15449: Illumos Illumos-Gate

Medium severity, CVSS 5.8. EPSS: 0.1% chance of exploitation in the next 30 days.

A time-of-check to time-of-use (TOCTOU) flaw in the illumos data-link pseudo-driver (dld) affects handling of the DLDIOC_GETMACPROP and DLDIOC_SETMACPROP ioctls on /dev/dld. drv_ioc_prop_common() in usr/src/uts/common/io/dld/dld_drv.c copies the dld_ioc_macprop_t ioctl header in once to read its pr_valsize field, sizes and allocates a kernel heap buffer from that value, and then copies the full request in a second time from the same unprivileged user address. A concurrent thread can enlarge pr_valsize between the two copyins, so the second copyin and the subsequent property handling write beyond the end of the undersized allocation and corrupt the kernel heap. An unprivileged local user, including one confined to a non-global zone that owns a datalink, can trigger this to panic the system. The resulting kernel heap corruption may be usable for further compromise.

Affected products

• Illumos Illumos-Gate
• Omnios Omnios: from r151058, before r151058j (fixed in r151058j); from r151056, before r151056aj (fixed in r151056aj); from r151054, before r151054bj (fixed in r151054bj)
• Triton Data Center Smartos

Published 2026-07-16. Last modified 2026-07-17.