CVE-2026-53249: ipv4: restrict IPOPT_SSRR and IPOPT_LSRR options

highCVSS 7CVE-2026-53249

CSIRTS triage

vendor: Linux product: Linux KernelOther

What: Restrictions on IPOPT_SSRR and IPOPT_LSRR options are necessary.
Who is affected: Deployments of the affected Linux kernel versions.
Urgency: Remediation is important due to the high severity rating.
Action: Update to the patched version of the Linux kernel.

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
Published: 2026-06-09
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-53249

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-2026-532490.12% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-53249	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

unknownMultiple vulnerabilities in Microsoft Azure Linux (June 29, 2026)cert-fr-avis

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