Arbitrary Command Injection Affecting jruby-9.4 package, versions <9.4.15.0-r2


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
0.43% (35th percentile)

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  • Snyk IDSNYK-WOLFILATEST-JRUBY94-18353266
  • published28 Jul 2026
  • disclosed9 May 2026

Introduced: 9 May 2026

CVE-2026-42257  (opens in a new tab)
CWE-77  (opens in a new tab)
CWE-93  (opens in a new tab)

How to fix?

Upgrade Wolfi jruby-9.4 to version 9.4.15.0-r2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream jruby-9.4 package and not the jruby-9.4 package as distributed by Wolfi. See How to fix? for Wolfi relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1