Linux kernel svcrdma affects NFS-over-RDMA in widely deployed kernels; can crash or enable kernel compromise—broad impact across many environments.
CVE-2026-89533
Linux svcrdma arithmetic bug lets crafted RDMA/NFS requests crash or corrupt the kernel.
Is CVE-2026-89533 being exploited?
Not confirmed. CVE-2026-89533 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 0.51% probability of exploitation in the next 30 days.
How severe is CVE-2026-89533?
CVE-2026-89533 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-2026-89533?
Yes. A fix has been recorded for CVE-2026-89533. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-89533 affect?
CVE-2026-89533 affects Linux kernel (svcrdma module), NFS-over-RDMA servers, Major Linux distributions with unpatched kernels prior to 2026-09-13. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-89533?
Apply vendor/kernel stable patches or upgrade kernel; disable svcrdma/NFS-over-RDMA if patching is delayed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attacker can send crafted NFS-over-RDMA requests causing u32 underflow, huge allocations and kernel memory corruption leading to crash (DoS) and potential RCE.
Immediate action required
- affected>= d7cc73972661be4a02a1b09f1d9b3283c6c05154 and < 6ee4dc7476b3abc92ec1d444533a559f33f59561
- affected>= d7cc73972661be4a02a1b09f1d9b3283c6c05154 and < a46b35f213c2426f5d6a0458a8f7e873fc59cdfd
- affected>= d7cc73972661be4a02a1b09f1d9b3283c6c05154 and < 4493c96bbd0068fadf69cbae8d13426202e34cdc
- affected>= d7cc73972661be4a02a1b09f1d9b3283c6c05154 and < 4a44c140cc2f3643a39e258bb0c0ab9d0f494f5e
- affected5.11
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.