Use-After-Free in Microsoft QUIC (CVE-2026-100219)
Summary
Vulnerability in Microsoft QUIC (CVE-2026-100219). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
Use after free in Microsoft QUIC allows an unauthorized attacker to execute code over a network.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A weakness called CVE-2026-100219 was discovered in Microsoft QUIC.
In plain terms, it is a use-after-free flaw that often leads to attacker takeover.
Severity is Critical (CVSS 9.8/10). If exploited, attackers can fully take over the affected system.
What you should do: update the affected software to the latest version. If unsure, ask your IT team or search the vendor's site for "Microsoft QUIC CVE-2026-100219".
CVE-2026-100219 (Microsoft QUIC). Severity: Critical / CVSSv3 9.8. Category: CWE-416.
Response plan:
- Check the vendor advisory for affected versions and the patched release.
- If a vulnerable version is running in production, schedule maintenance (urgency from KEV/CVSS).
- If no patch yet, mitigate via WAF rule, disabling the affected feature, etc.
- Monitor logs / SIEM for known IOC and PoC signatures of this CVE.
PoCs and fix commits: see the 'References' section, MITRE, and NVD.
A weakness (CVE-2026-100219) in Microsoft QUIC. In plain words, it is a use-after-free flaw that often leads to attacker takeover.
Target versions of Microsoft QUIC (see vendor advisory). If running in production, identify exposure immediately.
Severity: Critical (CVSS 9.8/10). If exploited, attackers can fully take over the affected system.
Update to the patched release as listed in the vendor advisory. (Typical mitigation pattern for CWE-416)
If a patch is not yet available, consider disabling the affected feature, applying WAF rules, blocking via network ACLs, or isolating the vulnerable version.
Check version information, scan dependencies via SBOM, and monitor SIEM for IOC and PoC signatures related to this CVE.
References
- web secure@microsoft.com
- web nvd.nist.gov
- web github.com