CVE 8.9 HIGH

Request Smuggling (TE.TE) in h3 v1_CVE-2026-23527

January 15, 2026 invoker category_cve

8.9 / 10

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L

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.

AI Analysis

HTTP Request Smuggling vulnerability due to case-sensitive check for the Transfer-Encoding header

Basic Information

ID CVE-2026-23527

Source GitHub_M

Published Jan 15, 2026 at 19:24

Modified Jan 15, 2026 at 20:00

Affected Product

Vendor h3js

Product h3

Version < 1.15.5

Affected Versions h3js h3 < 1.15.5

CWE Classification

CWE-444

AI Assessment

AI Score 8.9 / 10

AI Severity High

Vendor h3js

Product h3

Version < 1.15.5

References

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    "published": "2026-01-15T19:24:20.514Z",
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