CVE-2026-67353

guzzlehttp/guzzle versions before 7.15.1 contain a denial of service vulnerability in the CookieJar that accepts unlimited Set-Cookie header fields with no size restrictions. Attackers can return many large cookies from a malicious server, causing Guzzle to store excessive data in memory and generate oversized Cookie headers that fail in handlers or destination servers.

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 NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/guzzle/guzzle/security/advisories/GHSA-f283-ghqc-fg79
https://www.vulncheck.com/advisories/guzzlehttp-guzzle-before-unbounded-cookie-denial-of-service

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-01 13:17

Updated : 2026-09-08 20:35

NVD link : CVE-2026-67353

Mitre link : CVE-2026-67353

CVE.ORG link : CVE-2026-67353

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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