CVE-2026-67339

guzzlehttp/guzzle versions before 7.14.2 fail to properly isolate Proxy-Authorization headers from origin servers in cURL handlers. Attackers can capture proxy credentials through origin server access logs when requests are redirected, bypassed, or sent through SOCKS proxies that Guzzle misclassifies as direct connections.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/guzzle/guzzle/security/advisories/GHSA-94pj-82f3-465w
https://www.vulncheck.com/advisories/guzzlehttp-guzzle-before-proxy-authorization-header-disclosure

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-01 13:17

Updated : 2026-09-08 20:35

NVD link : CVE-2026-67339

Mitre link : CVE-2026-67339

CVE.ORG link : CVE-2026-67339

JSON object : View

Products Affected

No product.

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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