Description
H3 is a minimal H(TTP) framework built for high performance and portability. Prior to 1.15.5, there is a critical HTTP Request Smuggling vulnerability. readRawBody is doing a strict case-sensitive check for the Transfer-Encoding header. It explicitly looks for "chunked", but per the RFC, this header should be case-insensitive. This vulnerability is fixed in 1.15.5.
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L
- Attack Vector
- network
- Complexity
- high
- Privileges
- none
- User Action
- none
- Scope
- changed
- Confidentiality
- high
- Integrity
- high
- Availability
- low
- Weaknesses
- CWE-444
Metadata
- Primary Vendor
- H3
- Published
- 1/15/2026
- Last Modified
- 1/23/2026
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
h3 : h3
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