CVE-2026-72398: sctp: add INIT verification after cookie unpacking

highCVSS 8.1CVE-2026-72398

CSIRTS triage

product: sctp Authentication bypass

What: SCTP protocol handler missing INIT verification after cookie unpacking enables authentication bypass.
Who is affected: Linux systems with SCTP enabled and processing SCTP connections.
Urgency: High urgency; missing verification allows connection establishment without proper handshake validation.
Action: Apply kernel patch that adds INIT verification after cookie unpacking.

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 8.1
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-72398

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-2026-723980.70% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 51% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-72398	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

criticalCVE-2026-72398: In the Linux kernel, the following vulnerability has been resolved: sctp: add INIT verificatio…nvd

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