HTTP Request Smuggling Affecting python3-h2 package, versions <3.2.0-150200.3.8.1


Severity

Recommended
0.0
medium
0
10

Based on SUSE Linux Enterprise Server security rating.

Threat Intelligence

EPSS
0.42% (34th percentile)

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  • Snyk IDSNYK-SLES157-PYTHON3H2-19784303
  • published14 Sept 2026
  • disclosed4 Sept 2026

Introduced: 4 Sep 2026

CVE-2026-71554  (opens in a new tab)
CWE-444  (opens in a new tab)

How to fix?

Upgrade SLES:15.7 python3-h2 to version 3.2.0-150200.3.8.1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python3-h2 package and not the python3-h2 package as distributed by SLES. See How to fix? for SLES:15.7 relevant fixed versions and status.

h2 is a pure-Python implementation of a HTTP/2 protocol stack. Versions up to and including 4.4.0 accept request header blocks containing more than one Host header, and forward every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request carries two Host header lines, providing a request smuggling primitive. This issue is fixed in version 4.4.1.

CVSS Base Scores

version 3.1