Vulnerability in Excon

CVE-2026-54171

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.

EPSS: 0.004 (35.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-54171?
CVE-2026-54171 is a medium-severity vulnerability in Excon, classified under Insertion of Sensitive Information into Sent Data. CVSS score: 6.5/10. Published 2026-07-17.
How severe is CVE-2026-54171?
Medium severity. CVSS v3 base score is 6.5 out of 10.