Skip to content
Fencer Vulns
medium 6.8

CVE-2026-107399 json

Mechanize sends credential headers to another origin after a meta refresh

published 2026-10-08 31 d ago modified 2026-10-14 26 d ago also GHSA-c6rp-p8xm-4q9f , EUVD-2026-95318

cvss
6.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 30%
public exploits
0
none known

Summary

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.

Patch / fix

  • rubygems mechanize 2.14.1
  • ruby-mechanize Debian 14 2.14.1-1

debian advisories DEBIAN-CVE-2026-107399

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-107399 updated cvss 5.9

mechanize: mechanize: Information disclosure via cross-origin meta refresh

  • Red Hat 3scale API Management Platform 2 3scale-amp2/system-rhel8
    affected: workaround, no fix planned “Out of support scope”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
26 d ago

Exploit prediction

0.36% chance of exploitation in the next 30 days, higher than 30% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 6.8 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
GitHub 3.1 6.8 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
rubygems mechanize
<2.14.1
2.14.1

Affected products

  • sparklemotion mechanize

Classification

Weakness
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-522 Insufficiently Protected Credentials

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.