major vulnerability· requires attention

A Linux kernel NFS server race causes memory corruption and potential kernel RCE. Linux is ubiquitous on servers; this can disrupt enterprise infrastructure and requires org-wide attention.

Systems

CVE-2026-93221

8.1

High

EPSS 0.42%Patch available

Race in Linux nfsd can cause double-free leading to kernel memory corruption and possible RCE.

exploited

No known exploitation not in CISA KEV as of our last sync

fix

Fixed in < 5.2, >= 7.2.4 and <= 7.2.*, >= 7.3-rc1 and <= *

likelihood

EPSS 0.42%top 64% of scored CVEs

Published 24 Sept 2026Analysed here 26 Sept 2026CVSS scored by the publisher (CNA)

do firstUpgrade to a fixed release: < 5.2, >= 7.2.4 and <= 7.2.*, >= 7.3-rc1 and <= *.

common questions

Is CVE-2026-93221 being exploited?

Not confirmed. CVE-2026-93221 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 0.42% probability of exploitation in the next 30 days.

How severe is CVE-2026-93221?

CVE-2026-93221 is rated High with a CVSS score of 8.1. 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-2026-93221?

Yes. A fix has been recorded for CVE-2026-93221. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.

What does CVE-2026-93221 affect?

CVE-2026-93221 affects Linux kernel (nfsd - NFS server), Linux distributions using affected kernels, Servers exporting NFS shares. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.

What should I do about CVE-2026-93221?

Install vendor/kernel updates for nfsd and reboot NFS servers immediately.

Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.

executive summary

technical analysis

affected

Linux kernel (nfsd - NFS server)Linux distributions using affected kernelsServers exporting NFS shares

impact

Concurrent NFS operations can trigger double-free/memory corruption in nfsd, enabling remote code execution or kernel crash (DoS) on NFS servers.

action required

Immediate action required

affected versions

Linux

affected>= 362063a595be959bc08f4163e6405a0266740091 and < df5922fe09a8131c793ffa86adf204999b0470f8
affected>= 362063a595be959bc08f4163e6405a0266740091 and < 11a5fe42e1811f793e04ef885b639ea7668f439d
affected5.2

vendor says fixed in< 5.2, >= 7.2.4 and <= 7.2.*, >= 7.3-rc1 and <= *

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.

timeline

24 Sept 2026Published
26 Sept 2026Analysed by vulneraibility.com · 2 days later
21 Oct 2026CVE record last updated · 25 days later

how to fix

Remediation steps are tailored for users whose stack is affected. Add this technology to your stack to see the fix checklist.

references

NVD CVE.org CVE Details Source

5 references in the CVE record: 5 links

Linkgit.kernel.org /stable/c/94b450977c60261903c945419d2df4a464de60c4
Linkgit.kernel.org /stable/c/faac245ca739b66e96fb7bb43e21df537239a4e5
Linkgit.kernel.org /stable/c/40bab0da844c142431a6b1cc21b4cf53491dac44
Linkgit.kernel.org /stable/c/df5922fe09a8131c793ffa86adf204999b0470f8
Linkgit.kernel.org /stable/c/11a5fe42e1811f793e04ef885b639ea7668f439d

sources

CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
NVD: CVSS and CPE data
FIRST EPSS: exploit probability and percentile
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.

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