CVE-2026-64400: ksmbd: prevent path traversal bypass by restricting caseless retry
CSIRTS triage
- What
- This vulnerability prevents path traversal bypass by restricting caseless retry.
- Who is affected
- Deployments using the ksmbd server.
- Urgency
- Remediation is critical to prevent unauthorized file access, although no exploitation has been reported.
- Action
- Apply the patch for CVE-2026-64400.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64400
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-644000.36% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 28% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-64400 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
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