CVE-2026-46243: smb: client: reject userspace cifs.spnego descriptions

highCVSS 7.8CVE-2026-46243

CSIRTS triage

product: smbOther

What: Userspace cifs.spnego descriptions are not being rejected properly.
Who is affected: Deployments using smb are affected.
Urgency: Remediation is urgent due to the high severity of the vulnerability (CVSS 7.8).
Action: Update smb to the latest version.

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: high — CVSS 7.8
Published: 2026-06-09
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-46243

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-2026-462430.35% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 27% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-46243	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

medium[UPDATE] [medium] Linux Kernel: Vulnerability allows privilege escalationcert-bund
unknownUSN-8530-1: Linux kernel (AWS) vulnerabilitiesubuntu
unknownUSN-8529-1: Linux kernel vulnerabilitiesubuntu
unknownexploitedUSN-8528-1: Linux kernel (Xilinx ZynqMP) vulnerabilitiesubuntu
unknownUSN-8527-1: Linux kernel (Raspberry Pi) vulnerabilitiesubuntu
unknownUSN-8492-5: Linux kernel (FIPS) vulnerabilitiesubuntu
unknownMultiple vulnerabilities in Red Hat Linux kernel (July 10, 2026)cert-fr-avis
unknownUSN-8492-4: Linux kernel (Raspberry Pi) vulnerabilitiesubuntu
unknownUSN-8490-2: Linux kernel (Raspberry Pi) vulnerabilitiesubuntu
unknownMultiple vulnerabilities in Red Hat Linux kernel (July 3, 2026)cert-fr-avis
unknownRedHat Linux Kernel Multiple Vulnerabilitieshkcert

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