No VulnCrest analysis published for this CVE yet. Below is the original CNA/NVD description, unmodified.
Description
h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 4212ce114506a073505fd389db16ad2ba4e582a0, a client could send an incomplete CONNECT-UDP Capsule with an excessively large declared length, causing H2O to keep buffering received bytes without a per-Capsule limit while waiting for the remainder. Deployments that enabled proxy.connect-udp and accepted CONNECT-UDP requests could exhaust server memory and lose availability. This vulnerability is fixed with commit 4212ce114506a073505fd389db16ad2ba4e582a0.
Exploits & detection
No public PoC or detection template found yet.
Timeline
- Published: 04 Nov 2026
- Last modified upstream: 04 Nov 2026
Sources & licenses
- CVE / CVSS / CWE
- NVD record ↗ (unmodified). This product uses the NVD API but is not endorsed or certified by the NVD. CVE® © The MITRE Corporation.
- Exploitation
- CISA KEV (CC0) · EPSS by FIRST.org
- References used for the analysis
- Analysis, summary and remediation
- © VulnCrest