Kernel-level vulnerability in Linux CIFS (widely deployed); remote SMB/DFS input can crash or leak kernel memory and affect many servers/clients.
CVE-2026-72318
Kernel OOB read in CIFS DFS referral parsing (SMB client) causing info leak or DoS.
Is CVE-2026-72318 being exploited?
Not confirmed. CVE-2026-72318 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 0.59% probability of exploitation in the next 30 days.
How severe is CVE-2026-72318?
CVE-2026-72318 is rated Critical with a CVSS score of 9.4. 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-2026-72318?
Yes. A fix has been recorded for CVE-2026-72318. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-72318 affect?
CVE-2026-72318 affects Linux kernel (cifs module), SMB/CIFS clients, Linux distributions with CIFS enabled (Ubuntu, RHEL, SUSE, Debian). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-72318?
Apply vendor/kernel updates immediately; block untrusted SMB servers and restrict SMB access.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote malicious SMB/DFS server can trigger out-of-bounds kernel read via DFS referral parsing, causing kernel memory disclosure or crash (remote DoS).
Immediate action required
- affected>= 4ecce920e13ace16a5ba45efe8909946c28fb2ad and < 76c607b9353d377b1d1b11db50e743eee0ccf658
- affected>= 4ecce920e13ace16a5ba45efe8909946c28fb2ad and < d64b6be5740ce230aca184d8d224c75d9866045d
- affected>= 4ecce920e13ace16a5ba45efe8909946c28fb2ad and < 929a85932d14190988f1eafd6ee8cc68d66ace0b
- affected>= 4ecce920e13ace16a5ba45efe8909946c28fb2ad and < b784cd1c24d89bf71be2efe1e948ff7c03371e57
- affected>= 4ecce920e13ace16a5ba45efe8909946c28fb2ad and < c37abc99bb3de3d3219ecef253d649f74117fd83
- affected>= 4ecce920e13ace16a5ba45efe8909946c28fb2ad and < 027a84ac6b50c12ef767c15abfc58aa865820e9e
- affected4.11
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.