CVE-2026-65794: Windows SMB Client Information Disclosure Vulnerability

mediumCVSS 6.5CVE-2026-65794

Buffer over-read in Windows SMB Client allows an unauthorized attacker to disclose information over a network.

CSIRTS triage

vendor: Microsoft product: Windows SMB Client Information disclosure

What: A buffer over-read in Windows SMB Client allows remote information disclosure over the network.
Who is affected: Systems running Windows SMB Client with network connectivity are affected.
Urgency: Moderate urgency; CVSS 6.5 medium-high severity information disclosure over the network without authentication.
Action: Apply the latest Windows security update addressing CVE-2026-65794.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 6.5
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-65794

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-2026-657940.65% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 48% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-65794	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

unknownexploitedNCSC-2026-0284 [1.00] [M/H] Vulnerabilities patched in Microsoft Windowsncsc-nl
mediumCVE-2026-65794: Buffer over-read in Windows SMB Client allows an unauthorized attacker to disclose information…nvd

Recent advisories for Windows SMB Client

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

mediumCVE-2026-65794: Buffer over-read in Windows SMB Client allows an unauthorized attacker to disclose information…nvd · 2026-08-11
highCVE-2026-62799: Heap-based buffer overflow in Windows SMB Client allows an authorized attacker to elevate priv…nvd · 2026-08-11
mediumCVE-2026-62782: Out-of-bounds read in Windows SMB Client allows an unauthorized attacker to disclose informati…nvd · 2026-08-11
mediumCVE-2026-62782: Windows SMB Client Information Disclosure Vulnerabilitymsrc · 2026-08-11
highCVE-2026-62799: Windows SMB Client Elevation of Privilege Vulnerabilitymsrc · 2026-08-11
criticalexploitedCVE-2025-33073: Microsoft Windows SMB Client Improper Access Control Vulnerabilitycisa-kev · 2025-10-20