CVE-2026-15422
Remote kernel RCE via malformed SCTP INIT ACK in illumos networking stack.
Is CVE-2026-15422 being exploited?
Not confirmed. CVE-2026-15422 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.88% probability of exploitation in the next 30 days.
How severe is CVE-2026-15422?
CVE-2026-15422 is rated Critical with a CVSS score of 9.1. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-15422?
Yes. A fix has been recorded for CVE-2026-15422. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-15422 affect?
CVE-2026-15422 affects illumos (all distributions prior to illumos-gate commit 53a3efde), OpenIndiana, SmartOS, OmniOS. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-15422?
Apply illumos-gate updates (post-53a3efde) or vendor patches; block SCTP at edge if unused.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote unauthenticated attacker can send crafted SCTP INIT ACK causing OOB heap corruption and achieve kernel-level remote code execution.
Immediate action required
- affected>= a5407c02d5ed61b29481b9b71f1307d7ebec9e5c and < 53a3efdeff8e6745bbfb69c5360f94962fb79e75
- affected>= r151058 and < r151058j
- affected>= r151056 and < r151056aj
- affected>= r151054 and < r151054bj
- affected>= any and < r151054
- affected>= any and < 202060709
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.