CVE-2026-69245
Received
Received - Intake
Cookie Domain Spoofing in Guzzle HTTP Client
Vulnerability report for CVE-2026-69245, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-03
Last updated on: 2026-08-03
Assigner: GitHub, Inc.
Description
Description
Guzzle is an extensible PHP HTTP client. Prior to 7.15.2 and 8.0.1, SetCookie::matchesDomain() gives every subdomain of a cookie Domain that cookie unless SetCookie::matchesDomain() recognizes the Domain as an IP literal or a numeric host, and the decision comes from the domain's own text, so two spellings a transport reads as an address keep subdomain scope. Hexadecimal and mixed-base forms such as 0x7f000001 and 0177.0.0.0x1 go unrecognized while libcurl 8.21.0 reads both as 127.0.0.1. A percent-escaped Domain keeps that scope on both branches because percent-decoding sits above numeric parsing, so 192.168.0.%31 and 127.0.0.1%2e are registered names in the URI grammar rather than address literals, and no numeric rule in any base classifies them, while libcurl decodes the host before resolving and reads them as 192.168.0.1 and 127.0.0.1. A cookie stored for Domain=0x7f000001 is placed in the Cookie header of a request to evil.0x7f000001, disclosing a session identifier or token to a host that is not that address, and a response from evil.0x7f000001 setting Domain=0x7f000001 is accepted into the jar and replayed to the address, so a server answering for the look-alike name can fix a session or set application state. Exploitation requires the application to enable cookie support, address an origin by one of these spellings, and contact a host whose name ends in that spelling. This issue is fixed in versions 7.15.2 and 8.0.1.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| guzzle | guzzle | to 7.15.2 (exc) |
| guzzle | guzzle | to 8.0.1 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-384 | Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions. |
| CWE-180 | The product validates input before it is canonicalized, which prevents the product from detecting data that becomes invalid after the canonicalization step. |
| CWE-346 | The product does not properly verify that the source of data or communication is valid. |
