CVE-2026-64393

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 93% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 5 sources updated this week
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.1Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: run set info with opener credentials

SMB2 SET_INFO handlers call path-based VFS helpers after checking the access mask granted to the SMB handle. Those helpers perform their owner, inode permission and LSM checks using the current ksmbd worker credentials.

Run the complete SET_INFO dispatch with the credentials captured when the handle was opened. This also removes the separate security information credential setup and keeps all SET_INFO classes under one credential scope.

Direct override_creds() is used because it can nest with the request credential overrides already used by rename and link helpers.

CVSS v3
9.1
EG Score
9.1(medium)
EG Risk
46(Track)
EG Risk 46/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity91% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
7%
KEV
Not listed

Published

July 25, 2026

Last Modified

July 27, 2026

Advisory Details (6)

Auto-updated Jul 27, 2026
No patch confirmed yet.
generic

ksmbd: run set info with opener credentials - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b383bcad3d2fe634b26efbce53e22bbb5753a520
generic

ksmbd: run set info with opener credentials - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/8cc9ec711f5255167247a9ab6a7179b787426ed7
generic

ksmbd: run set info with opener credentials - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/20ee516a62989a8d505ee432f9e59525ea23984e
generic

ksmbd: run set info with opener credentials - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0ce682867fd506f61f40c76bde7e4205bde34e87
generic

ksmbd: run set info with opener credentials - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b35afd5cf8fab236ef21117e42ee45691d4ffa7b
generic

ksmbd: run set info with opener credentials - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/5cbabf3a71575cd31bc7785d92d4ab42338a654b

Vendor Advisories for CVE-2026-64393(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Data Freshness Timeline

(refreshed 14× in last 7d / 14× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-27 05:28 UTCEG score recompute
  2. 2026-07-27 05:28 UTCGHSA enrichment
  3. 2026-07-27 05:16 UTCEG score recompute▲ 9.10
  4. 2026-07-27 05:16 UTCGHSA enrichment
  5. 2026-07-27 05:12 UTCMITRE cvelistV5CVSS v3 → 9.1 · severity → CRITICAL
  6. 2026-07-26 14:54 UTCEPSS rescore
  7. 2026-07-26 14:54 UTCEPSS rescore
  8. 2026-07-26 02:48 UTCEG score recompute
  9. 2026-07-26 02:48 UTCGHSA enrichment
  10. 2026-07-25 14:18 UTCEPSS rescore
  11. 2026-07-25 14:18 UTCEPSS rescore
  12. 2026-07-25 10:39 UTCNVD update
  13. 2026-07-25 09:32 UTCEG score recompute
  14. 2026-07-25 09:21 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-64393?
CVE-2026-64393 is a critical vulnerability published on July 25, 2026. In the Linux kernel, the following vulnerability has been resolved: ksmbd: run set info with opener credentials SMB2 SET_INFO handlers call path-based VFS helpers after checking the access mask granted to the SMB handle. Those helpers perform their owner, inode permission and LSM checks using the…
When was CVE-2026-64393 disclosed?
CVE-2026-64393 was first published in the National Vulnerability Database on July 25, 2026, with the most recent update on July 27, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-64393 actively exploited?
CVE-2026-64393 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 93.1% of all scored CVEs.
What is the CVSS score of CVE-2026-64393?
CVE-2026-64393 has a CVSS v3 base score of 9.1 (NVD).
How do I remediate CVE-2026-64393?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-64393, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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