CVE-2026-55767
Description
A flaw was found in Guzzle, an extensible PHP HTTP client. The CookieJar component incorrectly accepted cookies with dot-only or whitespace-padded domain attributes. This vulnerability allows an attacker-controlled origin, when an application requests it with a shared cookie jar, to set a cookie that Guzzle may later send to unrelated hosts using the same jar. This could lead to cookie injection or session fixation against downstream services, potentially compromising user sessions or injecting malicious data.
Statement
Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.
Understanding the Weakness (CWE)
Access Control,Other
Technical Impact: Gain Privileges or Assume Identity; Varies by Context
An attacker can access any functionality that is inadvertently accessible to the source.
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