CRLF Injection Affecting localstack package, versions <4.7.0-r5


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.06% (20th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LOCALSTACK-12225980
  • published28 Aug 2025
  • disclosed25 Aug 2025

Introduced: 25 Aug 2025

NewCVE-2025-57804  (opens in a new tab)
CWE-93  (opens in a new tab)

How to fix?

Upgrade Chainguard localstack to version 4.7.0-r5 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream localstack package and not the localstack package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

h2 is a pure-Python implementation of a HTTP/2 protocol stack. Prior to version 4.3.0, an HTTP/2 request splitting vulnerability allows attackers to perform request smuggling attacks by injecting CRLF characters into headers. This occurs when servers downgrade HTTP/2 requests to HTTP/1.1 without properly validating header names/values, enabling attackers to manipulate request boundaries and bypass security controls. This issue has been patched in version 4.3.0.

CVSS Base Scores

version 3.1