Kernel-level use-after-free in the widely deployed Linux DLM subsystem can disrupt infrastructure and enable kernel compromise; requires org‑wide attention.
CVE-2026-74401
Linux kernel DLM ordering bug causes use-after-free; kernel crash or RCE risk.
Is CVE-2026-74401 being exploited?
Not confirmed. CVE-2026-74401 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 0.44% probability of exploitation in the next 30 days.
How severe is CVE-2026-74401?
CVE-2026-74401 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-2026-74401?
Yes. A fix has been recorded for CVE-2026-74401. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-74401 affect?
CVE-2026-74401 affects Linux kernel (DLM subsystem), Cluster nodes using DLM/clustered filesystems, Nodes exposing DLM messaging over network. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-74401?
Install kernel DLM patch/update and reboot affected nodes; restrict/block DLM network access until patched.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Use-after-free in DLM send_queue via networked DLM messages — can cause kernel crash, privilege escalation, or remote code execution.
Immediate action required
- affected>= 489d8e559c6596eb08e16447d9830bc39afbe54e and < ae9e534e502a0f48c12baf83608c5de0ff0eab11
- affected>= 489d8e559c6596eb08e16447d9830bc39afbe54e and < 6369619f1b665f12d8c99cc6ff733c64eb08b22e
- affected>= 489d8e559c6596eb08e16447d9830bc39afbe54e and < 712714f818d83373847874ab0f8e426be79296cf
- affected>= 489d8e559c6596eb08e16447d9830bc39afbe54e and < 4d45250b1d22960f86d83245be188b16e456218b
- affected>= 489d8e559c6596eb08e16447d9830bc39afbe54e and < d2248cb70c070f8f04762872772e155b59016f17
- affected5.14
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.