Linux kernel netfilter vulnerability impacts core OS networking used across servers, cloud VMs, appliances and containers; widespread and could disrupt infrastructure if exploited.
CVE-2026-72442
Linux kernel netfilter IPv6-in-IPv6 handling bug can crash or compromise hosts.
Is CVE-2026-72442 being exploited?
Not confirmed. CVE-2026-72442 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 0.55% probability of exploitation in the next 30 days.
How severe is CVE-2026-72442?
CVE-2026-72442 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-2026-72442?
Yes. A fix has been recorded for CVE-2026-72442. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-72442 affect?
CVE-2026-72442 affects Linux kernel (netfilter flowtable / IP6IP6), Major Linux distros (Ubuntu, Debian, RHEL, SUSE, CentOS), Cloud VMs, routers, and appliances using affected kernels. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-72442?
Apply vendor kernel/security updates or backported fix immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Crafted IPv6-in-IPv6 packets may trigger kernel out-of-bounds access leading to remote kernel crash (DoS) and potential privilege escalation/RCE in some cases.
Immediate action required
- affected>= d98103575dcdd3a730e0901ab457791a9ac6930c and < 7f8d816a9aa2729d270418f00c9ef5e85bfc1b31
- affected>= d98103575dcdd3a730e0901ab457791a9ac6930c and < f4c2d8668d85ed125985da663c824a9c25498257
- affected7.0
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.