CVE-2026-86250: Uncontrolled Resource Consumption in h3js h3
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.
CVE-2026-86250: Uncontrolled Resource Consumption in h3js h3
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.
CVSS v4.0
Score 8.7high
Affected software
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-06T11:35:19.316Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a9d5b10acd9273b49b9c58a
Added to database: 09/06/2026, 12:22:40 UTC
Last updated: 09/07/2026, 00:18:17 UTC
Views: 12
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