CVE-2026-107399

Mechanize sends credential headers to another origin after a meta refresh

Published Oct 8, 2026 CVSS 3.1 · 6.8 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-c6rp-p8xm-4q9f Mechanize sends credential headers to another origin after a meta refresh
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Sparklemotion
Sparklemotion mechanize
Vendors & Products Sparklemotion
Sparklemotion mechanize
Type Values Removed Values Added
Description 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.
Title Mechanize sends credential headers to another origin after a meta refresh
Weaknesses CWE-200
CWE-522
References
Metrics cvssV3_1

{'score': 6.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 14, 2026, 1:21 AM
Reserved
Oct 7, 2026, 9:07 PM
Status
Deferred
Published
Oct 8, 2026, 10:17 PM
Modified
Oct 14, 2026, 2:16 AM
Severity
Moderate
Public date
Oct 8, 2026, 9:24 PM