What’s Vulnerable › Vulnerabilities

CVE-2026-54171: Excon: redact additional sensitive/risky headers when following redirects

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-17 · updated 2026-07-29
• Weakness: CWE-201

Description

Excon is usable, fast, simple HTTP 1.1 for Ruby. Prior to 1.5.0, Excon's RedirectFollower middleware failed to strip additional sensitive headers when following redirects and did not provide a custom list of headers to strip. This could cause inadvertent leakage of sensitive data when the initial request includes header information that is not intended for the new target. This issue is fixed in version 1.5.0.

Affected products

• excon: before 1.5.0 — fixed in 1.5.0
• Rubygems Excon: before 1.5.0; 0.0.1, 0.0.10, 0.0.11, 0.0.12, 0.0.13, 0.0.14 (+272) — fixed in 1.5.0

How to fix

Upgrade to a fixed version: excon 1.5.0; Rubygems Excon 1.5.0. Check the vendor advisory for mitigations.

References

• https://github.com/excon/excon/commit/ea89a35308a12f4b791b6c50f2cbd33f94889fa3
• https://github.com/excon/excon/pull/901
• https://github.com/excon/excon/security/advisories/GHSA-48rx-c7pg-q66r

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