CVE-2026-74608: smb: client: Fix use-after-free in cifs_try_adding_channels()

mediumCVSS 5.3CVE-2026-74608

CSIRTS triage

vendor: Linux product: Linux Kernel Memory corruption

What: Use-after-free vulnerability in the SMB client cifs_try_adding_channels() function.
Who is affected: Systems using the Linux SMB client stack for mounting CIFS shares on vulnerable kernels.
Urgency: Medium urgency; not currently exploited but use-after-free can lead to crashes or information disclosure.
Action: Apply kernel patch fixing the use-after-free in cifs_try_adding_channels() or update to a patched kernel 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: medium — CVSS 5.3
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-74608

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-2026-746080.48% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 39% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-74608	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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