CVE-2026-107399

MEDIUM 6.8

Mechanize sends credential headers to another origin after a meta refresh

CVSS Score

6.8

EPSS Score

0.0%

EPSS Percentile

0th

The Mechanize library is used for automating interaction with websites. Prior to 2.14.1, Mechanize applies no origin trust boundary in Mechanize::HTTP::Agent#response_follow_meta_refresh when Mechanize#follow_meta_refresh is enabled. A page containing a meta refresh to another origin causes headers configured through Mechanize#request_headers= to be reapplied to the refresh request, allowing an attacker who controls content in the crawl to capture bearer tokens or session cookies. The default configuration is not affected because follow_meta_refresh is false, and the exposure is limited to caller-supplied default headers. This issue is fixed in version 2.14.1.

CWE	CWE-200 CWE-522
Vendor	sparklemotion
Product	mechanize
Published	Oct 8, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

None

Availability

None

Affected Versions

sparklemotion / mechanize

< 2.15.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/sparklemotion/mechanize/security/advisories/GHSA-c6rp-p8xm-4q9f github.com: https://github.com/sparklemotion/mechanize/pull/676 github.com: https://github.com/sparklemotion/mechanize/commit/02a1235842d6eda8d4a5a3d8f13aba2cecf52e4f github.com: https://github.com/sparklemotion/mechanize/commit/84c74df87d15f5d119df268ba6aa79bc1e16a2c3 github.com: https://github.com/sparklemotion/mechanize/releases/tag/v2.14.1