CVE-2026-105221 PUBLISHED

The gist RubyGem before 6.1.0 contains an improper certificate validation vulnerability that allows on-path attackers to intercept HTTPS traffic because http_connection in lib/gist.rb sets VERIFY_NONE. Attackers can present any certificate to read or modify GitHub API traffic, stealing OAuth tokens and login credentials to read and modify the victim's gists.

• Siyang Wu finder

• GitHub Issue #373
• https://github.com/defunkt/gist
• https://github.com/defunkt/gist/blob/v6.0.0/lib/gist.rb#L466-L468
• https://github.com/defunkt/gist/commit/07ccc1a6d46e9d36f0e85d0b1c5d795890ae6bcf
• VulnCheck Advisory: Gist RubyGem before 6.1.0 Disabled TLS Certificate Verification

• Improper Certificate Validation CWE