What is GHSA-fg72-q65g-wm5w?

GHSA-fg72-q65g-wm5w is a security advisory published by GitHub Security Advisories with High severity. h3 versions before 2.0.1-rc.18 fail to validate the chunk count parsed from user-controlled...

Which CVE IDs does GHSA-fg72-q65g-wm5w cover?

GHSA-fg72-q65g-wm5w covers the following CVE IDs: CVE-2026-86250. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-fg72-q65g-wm5w?

GHSA-fg72-q65g-wm5w has a CVSS v3 base score of 7.5, published by GitHub Security Advisories.

GHSA-fg72-q65g-wm5wHighCVSS 7.5

h3 versions before 2.0.1-rc.18 fail to validate the chunk count parsed from user-controlled...

Vendor

GitHub Security Advisories

Published

September 6, 2026

Last Modified

September 6, 2026

🔗 CVE IDs covered (1)

CVE-2026-86250 →

📋 Description

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 (4)

https://github.com/h3js/h3/security/advisories/GHSA-q5pr-72pq-83v3
https://nvd.nist.gov/vuln/detail/CVE-2026-86250
https://www.vulncheck.com/advisories/h3-before-2.0.1-rc.18-denial-of-service-via-unbounded-chunked-cookie
https://github.com/advisories/GHSA-fg72-q65g-wm5w