HIGHCVSS 8.7
CVE-2026-86250
CVE-2026-86250 updated by NVD
Summary
h3 versions before 2.0.1-rc.18 fail to validate the chunk count parsed from user-controlled cookie values in setChunkedCookie() and deleteChunkedCookie() functions. Attackers can send a crafted cookie header with an extremely large chunk count to trigger an O(n²) cleanup loop that hangs the server process.
References
Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.
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