CVE-2026-53183: mptcp: allow subflow rcv wnd to shrink
CSIRTS triage
- What
- The subflow receive window can shrink unexpectedly.
- Who is affected
- Deployments using mptcp are affected.
- Urgency
- Remediation is medium priority due to the medium severity of the issue.
- Action
- Apply the fix for CVE-2026-53183.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-53183
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-2026-531830.51% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 40% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-53183 | 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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