cvedb.io
CVE-2026-55767
MEDIUM · CVSS 5.8
EPSS exploitation probability: 0%
Published 2026-06-23T16:17:03.263 · Last modified 2026-06-26T19:34:41.340

Summary

Guzzle is an extensible PHP HTTP client. Prior to 7.12.1, CookieJar incorrectly accepts cookies with a dot-only Domain attribute and whitespace-padded variants. SetCookie::matchesDomain() removes leading dots from the cookie domain, normalizing dot-only values to the empty string; SetCookie::validate() only rejected a strictly empty domain, so these cookies could be stored and the empty normalized domain was treated as matching any request host. An attacker-controlled origin that an application requests with a shared cookie jar can therefore set a cookie that Guzzle later sends to unrelated hosts using the same jar. This may allow cookie injection or session fixation against downstream services, depending on how those services interpret the injected cookie. This vulnerability is fixed in 7

Affected products

guzzlephp — guzzle

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.