Published Jul 17, 2026Sources checked Oct 28, 2026
6.5MEDIUMCVSS out of 10
What this means
Review the available evidence
CVE-2026-54171 and is rated Medium severity with a CVSS score of 6.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
What to do next
Remediation and response
Microsoft Security Response Center guidance
Vendor revision: Aug 13, 2026
CBL-Mariner Releases
Vendor-listed releases
0.102.0-2
CISA KEVNot listedBased on the latest collected catalog
EPSS0.4%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is 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.