CVE-2026-42258 (GCVE-0-2026-42258)

Vulnerability from cvelistv5 – Published: 2026-05-09 19:40 – Updated: 2026-05-11 14:57
VLAI?
Title
net-imap: Command Injection via unvalidated Symbol inputs
Summary
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, symbol arguments to commands are vulnerable to a CRLF Injection / IMAP Command injection via Symbol arguments passed to IMAP commands. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
Severity ?
5.8 (Medium)
CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N
CWE
  • CWE-77 - Improper Neutralization of Special Elements used in a Command ('Command Injection')
  • CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
Assigner
References
Impacted products
Vendor Product Version
ruby net-imap Affected: < 0.4.24
Affected: >= 0.5.0, < 0.5.14
Affected: >= 0.6.0, < 0.6.4
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.



Detection rules are retrieved from Rulezet.