CVE-2026-42257 (GCVE-0-2026-42257)

Vulnerability from cvelistv5 – Published: 2026-05-09 19:39 – Updated: 2026-05-13 19:33
VLAI
Title
net-imap: Command Injection via "raw" arguments to multiple commands
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, several Net::IMAP commands accept a raw string argument that is sent to the server without validation or escaping. If this string is derived from user-controlled input, it may contain contain CRLF sequences, which an attacker can use to inject arbitrary 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:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
  • CWE-77 - Improper Neutralization of Special Elements used in a Command ('Command 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.

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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.
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