CVE-2026-21439 (GCVE-0-2026-21439)

Vulnerability from cvelistv5 – Published: 2026-01-05 23:51 – Updated: 2026-01-06 19:01
VLAI?
Title
badkeys vulnerable to ASCII control character injection on console via malformed input
Summary
badkeys is a tool and library for checking cryptographic public keys for known vulnerabilities. In versions 0.0.15 and below, an attacker may inject content with ASCII control characters like vertical tabs, ANSI escape sequences, etc., that can create misleading output of the badkeys command-line tool. This impacts scanning DKIM keys (both --dkim and --dkim-dns), SSH keys (--ssh-lines mode), and filenames in various modes. This issue is fixed in version 0.0.16.
Severity ?
2 (Low)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
CWE
  • CWE-150 - Improper Neutralization of Escape, Meta, or Control Sequences
Assigner
References
Impacted products
Vendor Product Version
badkeys badkeys Affected: < 0.0.16
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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