CVE-2026-59882 (Medium) detected in guzzlehttp/psr7-2.9.x-dev

[mend-bolt-for-github]

CVE-2026-59882 - Medium Severity Vulnerability

Vulnerable Library - guzzlehttp/psr7-2.9.x-dev

PSR-7 message implementation that also provides common utility methods

Library home page: https://api.github.com/repos/guzzle/psr7/zipball/7d0ed42f28e42d61352a7a79de682e5e67fec884

Dependency Hierarchy:

• guzzlehttp/guzzle-7.10.0 (Root Library)
  • ❌ guzzlehttp/psr7-2.9.x-dev (Vulnerable Library)

Found in HEAD commit: 81f84f058af0cbca57ee22476557ded21c6813aa

Found in base branch: master

Vulnerability Details

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.3, Uri::assertValidHost() does not reject URI host components containing authority delimiters, embedded ports, or malformed IPv6 brackets, allowing Uri::getHost() to disagree with the URI authority used for security or routing decisions. This issue is fixed in version 2.12.3.

Publish Date: 2026-07-08

URL: CVE-2026-59882

CVSS 3 Score Details (4.2)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: High
  • Privileges Required: None
  • User Interaction: Required
  • Scope: Unchanged
• Impact Metrics:
  • Confidentiality Impact: Low
  • Integrity Impact: Low
  • Availability Impact: None

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Origin: GHSA-c2w2-prh8-qm98

Release Date: 2026-07-08

Fix Resolution: guzzlehttp/psr7 - 2.12.3

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