CVE-2026-62898: Microsoft QUIC Information Disclosure Vulnerability
Use after free in Microsoft QUIC allows an unauthorized attacker to disclose information over a network.
CSIRTS triage
- What
- A use-after-free vulnerability in Microsoft QUIC allows unauthorized attackers to disclose information over the network.
- Who is affected
- Systems running affected QUIC implementations exposed to network-based information disclosure attacks.
- Urgency
- High severity (CVSS 7.5) with network exposure and information disclosure risk; prompt patching is required.
- Action
- Apply security updates to Microsoft QUIC components.
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-2026-62898
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.
- Moderate exploitation riskCVE-2026-628981.1% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 63% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-62898 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- high[NEW] [high] Microsoft Developer Tools: Multiple Vulnerabilitiescert-bund
- unknownMultiple vulnerabilities in Microsoft .Net (August 12, 2026)cert-fr-avis
- unknownMultiple vulnerabilities in Microsoft products (August 12, 2026)cert-fr-avis
- highGHSA-c494-m2fq-59mx: Microsoft Security Advisory CVE-2026-62898 – .NET Information Disclosure Vulnerabilityghsa
- highCVE-2026-62898: Use after free in Microsoft QUIC allows an unauthorized attacker to disclose information over …nvd
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