CVE-2026-16834
Integer underflow in IBM AIX/PowerVM allows remote denial of service.
Is CVE-2026-16834 being exploited?
Not confirmed. CVE-2026-16834 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 0.46% probability of exploitation in the next 30 days.
How severe is CVE-2026-16834?
CVE-2026-16834 is rated Critical with a CVSS score of 9.8. 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-2026-16834?
Yes. A fix has been recorded for CVE-2026-16834. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-16834 affect?
CVE-2026-16834 affects IBM AIX 7.2, IBM AIX 7.3, IBM PowerVM VIOS 4.1, IBM Power Systems running affected OS/VIOS. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-16834?
Apply vendor patch when available; restrict access to affected hosts and isolate management networks.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attacker can trigger an integer underflow to crash or hang AIX/VIOS hosts, causing service outages and system unavailability.
Immediate action required
- affected7.2
- affected7.3
- affected4.1
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.