This flaw allows a malicious HTTP server to set "super cookies" in curl that are then passed back to more origins than what is otherwise allowed or possible. This allows a site to set cookies that then would get sent to different and unrelated sites and domains. It could do this by exploiting a mixed case flaw in curl's function that verifies a given cookie domain against the Public Suffix List (PSL). For example a cookie could be set with `domain=co.UK` when the URL used a lower case hostname `curl.co.uk`, even though `co.uk` is listed as a PSL domain.
History

Tue, 12 May 2026 12:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 12 May 2026 11:30:00 +0000


Wed, 16 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00318}

epss

{'score': 0.00432}


Mon, 30 Jun 2025 17:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-178

Thu, 13 Feb 2025 17:30:00 +0000

Type Values Removed Values Added
Description This flaw allows a malicious HTTP server to set "super cookies" in curl that are then passed back to more origins than what is otherwise allowed or possible. This allows a site to set cookies that then would get sent to different and unrelated sites and domains. It could do this by exploiting a mixed case flaw in curl's function that verifies a given cookie domain against the Public Suffix List (PSL). For example a cookie could be set with `domain=co.UK` when the URL used a lower case hostname `curl.co.uk`, even though `co.uk` is listed as a PSL domain. This flaw allows a malicious HTTP server to set "super cookies" in curl that are then passed back to more origins than what is otherwise allowed or possible. This allows a site to set cookies that then would get sent to different and unrelated sites and domains. It could do this by exploiting a mixed case flaw in curl's function that verifies a given cookie domain against the Public Suffix List (PSL). For example a cookie could be set with `domain=co.UK` when the URL used a lower case hostname `curl.co.uk`, even though `co.uk` is listed as a PSL domain.

cve-icon MITRE

Status: PUBLISHED

Assigner: hackerone

Published:

Updated: 2026-05-12T10:52:38.819Z

Reserved: 2023-10-19T01:00:12.854Z

Link: CVE-2023-46218

cve-icon Vulnrichment

Updated: 2024-08-02T20:37:40.148Z

cve-icon NVD

Status : Modified

Published: 2023-12-07T01:15:07.160

Modified: 2026-05-12T11:16:14.360

Link: CVE-2023-46218

cve-icon Redhat

Severity : Moderate

Publid Date: 2023-12-06T07:00:00Z

Links: CVE-2023-46218 - Bugzilla