CVE-2026-107399 · GHSA-c6rp-p8xm-4q9f
Mechanize sends credential headers to another origin after a meta refresh
- Risk score
- 47/100
- CVSS
- 6.8 v3.1
- Exploit chance (30 days)
- 0.4%
- Published
- 8 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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 …
- Affected
- mechanize (rubygems) < 2.14.1
- Fix
- Upgrade mechanize to 2.14.1 or later.
- Exploitation
- No known exploitation
Story map
At a glance
mechanize: Yellow, plan it in. The Mechanize library is used for automating interaction with websites. Prior to 2.14.1, Mechanize sends caller-supplied credential headers to a different host after an HTTP redirect. Mechanize#request_headers= is reapplied by Mechanize::HTTP::Agent#request_add_headers even after Mechanize::HTTP::Agent#response_redire…
The flaws
- CVE-2026-107399: Mechanize sends credential headers to another origin after a meta refresh (CVSS 6.8 · EPSS 0%)
- CVE-2026-107715: Mechanize sends credential headers to another host after an HTTP redirect (CVSS 6.8 · EPSS 0%)
The fix
Upgrade mechanize: 2.14.1 or later on your release line
Who is exposed: mechanize (rubygems) < 2.14.1
Where it stands
- No known exploitation
Connects to
- Same weakness: Information disclosure (CWE-200). 196 other warnings in 30 days
Why it is Yellow
- CVSS 6.8 medium
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| mechanize | rubygems | < 2.14.1 | 2.14.1 |
References
- https://github.com/advisories/GHSA-c6rp-p8xm-4q9f
- https://github.com/sparklemotion/mechanize/security/advisories/GHSA-c6rp-p8xm-4q9f
- https://github.com/sparklemotion/mechanize/pull/676
- https://github.com/sparklemotion/mechanize/commit/02a1235842d6eda8d4a5a3d8f13aba2cecf52e4f
- https://github.com/sparklemotion/mechanize/commit/84c74df87d15f5d119df268ba6aa79bc1e16a2c3
- https://github.com/sparklemotion/mechanize/releases/tag/v2.14.1
- https://github.com/advisories/GHSA-c6rp-p8xm-4q9f
Original 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.
Last activity 8 Oct 2026. Patch Forecast updates every hour.