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Fencer Vulns
none 0.0

CVE-2026-33637 json

Faraday: Protocol-relative URI objects still bypass host scoping (possible incomplete fix for GHSA-33mh-2634-fwr2)

published 2026-05-18 5 mo ago modified 2026-09-10 1 mo ago also EUVD-2026-30966 , GHSA-5rv5-xj5j-3484

cvss
0.0
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 19%
public exploits
0
none known

Summary

Faraday is an HTTP client library abstraction layer that provides a common interface over many adapters. Versions 2.0.0 through 2.14.1 still allow protocol-relative host override when the request target is passed as a URI object (rather than a String) to Faraday::Connection#build_exclusive_url. This bypasses the February 2026 fix for GHSA-33mh-2634-fwr2 and enables off-host request forgery: a request built from a fixed-base Faraday::Connection can be redirected to an attacker-controlled host, forwarding connection-scoped values such as Authorization headers and default query parameters. This issue has been fixed in version 2.14.3.

Patch / fix

  • rubygems faraday 2.14.2
  • faraday_project faraday 2.14.2
  • ruby-faraday Debian 14 2.14.3-1

debian advisories DEBIAN-CVE-2026-33637

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-2026-33637 updated cvss 6.3

faraday: rubygem-faraday: Faraday: Off-host request forgery due to protocol-relative host override

  • Red Hat 3scale API Management Platform 2 3scale-amp21/zync, 3scale-amp22/zync, 3scale-amp21/system, 3scale-amp22/system, 3scale-amp2/zync-rhel8, 3scale-amp2/zync-rhel9, +3 more Red Hat Satellite 6 rubygem-faraday
    affected: workaround, no fix available “Ensure that request targets passed to Faraday connections use String types rather than URI objects. Validate and sanitize all user-controlled input before using it to construct HTTP request targets.”

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
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
5 mo ago

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/lostisland/faraday/security/advisories/GHSA-5rv5-xj5j-3484 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 0.0 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N
GitHub 3.1 0.0 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Affected packages

ecosystem package affected fixed in
rubygems faraday
>=2.0.0, <2.14.2
2.14.2

Affected products

  • lostisland faraday

Classification

Weakness
  • CWE-918 Server-Side Request Forgery

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.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.