CSIRTS // UNIFIED SECURITY ADVISORY FEEDSYS ● ONLINE · POWERED BY INTELFUSIONS.COM

← Back to feed

CVE-2026-9545: exposing HTTP/3 early data

highCVSS 7.5CVE-2026-9545

CSIRTS triage

Information disclosure
What
This vulnerability exposes HTTP/3 early data.
Who is affected
Users of systems utilizing HTTP/3 that may be affected by early data exposure.
Urgency
Remediation is urgent due to the high severity and potential for information disclosure.
Action
Implement mitigations for CVE-2026-9545.

AI-assisted analysis generated from the source advisory — verify against the original.

Details

Source
Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity
high — CVSS 7.5
Published
2026-07-02
Exploitation
Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-9545

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.

Referenced CVEs

CVECSIRTS overviewExternal
CVE-2026-9545coverage & exploitation statusNVD · CVE.org

Same CVEs, other sources

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

More from Microsoft Security Response Center