Name: CVE-2026-42246: Missing Report of Error Condition
Creator: Rapid7
Published: 2026-05-09T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-42246, CWE-636, CWE-754, CWE-393, CWE-325, CWE-392, CWE-841, CVSS 7.4, EPSS 0.00312

Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4.

CVSS Details

CVSS 4.0 Base Score: 7.6 (HIGH)
CVSS 4.0 Vector: (CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)
CVSS 3.1 Base Score: 7.4
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alma_linux	—	Upgrade rubygem-net-telnetUpgrade rubygem-rdocUpgrade ruby-bundled-gemsUpgrade rubygem-rexmlUpgrade rubygem-test-unitUpgrade rubygem-mongoUpgrade rubygem-bsonUpgrade rubygem-rbsUpgrade rubygem-rssUpgrade rubygem-jsonUpgrade ruby-default-gemsUpgrade rubygem-bson-docUpgrade rubygem-pgUpgrade rubygem-typeprofUpgrade rubygem-psychUpgrade rubygem-minitestUpgrade rubygem-mysql2Upgrade rubygem-abrt-docUpgrade rubygem-bundler-docUpgrade ruby-libsUpgrade rubygem-power_assertUpgrade rubygem-opensslUpgrade rubygemsUpgrade rubygem-xmlrpcUpgrade rubygem-pg-docUpgrade rubygem-mongo-docUpgrade rubygem-rakeUpgrade ruby-irbUpgrade rubygem-did_you_meanUpgrade rubygem-io-consoleUpgrade ruby-develUpgrade ruby-docUpgrade rubygem-irbUpgrade rubygem-bigdecimalUpgrade rubyUpgrade rubygem-raccUpgrade rubygem-mysql2-docUpgrade rubygem-abrtUpgrade rubygem-bundlerUpgrade rubygems-devel	Jul 2, 2026	Jun 30, 2026
Amazon Linux Ami 2	—	Upgrade rubygem-rdocUpgrade rubygem-jsonUpgrade ruby-debuginfoUpgrade rubygem-io-consoleUpgrade ruby-develUpgrade rubygem-rakeUpgrade ruby-docUpgrade rubygem-bigdecimalUpgrade rubyUpgrade ruby-irbUpgrade rubygem-minitestUpgrade ruby-libsUpgrade rubygems-develUpgrade ruby-tcltkUpgrade rubygem-psychUpgrade rubygems	Jul 8, 2026	Jul 8, 2026
Amazon_linux_2023	—	Upgrade ruby4.0-debuginfoUpgrade ruby4.0-default-gemsUpgrade ruby4.0-rubygem-test-unitUpgrade ruby4.0-rubygem-power_assertUpgrade ruby4.0Upgrade ruby4.0-rubygems-develUpgrade ruby4.0-bundled-gems-debuginfoUpgrade ruby4.0-rubygemsUpgrade ruby4.0-rubygem-minitestUpgrade ruby4.0-rubygem-io-console-debuginfoUpgrade ruby4.0-rubygem-typeprofUpgrade ruby4.0-rubygem-json-debuginfoUpgrade ruby4.0-rubygem-bundlerUpgrade ruby4.0-docUpgrade ruby4.0-develUpgrade ruby4.0-rubygem-psych-debuginfoUpgrade ruby4.0-debugsourceUpgrade ruby4.0-rubygem-rbs-debuginfoUpgrade ruby4.0-rubygem-psychUpgrade ruby4.0-rubygem-rdocUpgrade ruby4.0-rubygem-rakeUpgrade ruby4.0-rubygem-racc-debuginfoUpgrade ruby4.0-rubygem-irbUpgrade ruby4.0-bundled-gemsUpgrade ruby4.0-rubygem-rbsUpgrade ruby4.0-rubygem-raccUpgrade ruby4.0-rubygem-rexmlUpgrade ruby4.0-libs-debuginfoUpgrade ruby4.0-libsUpgrade ruby4.0-rubygem-bigdecimalUpgrade ruby4.0-rubygem-bigdecimal-debuginfoUpgrade ruby4.0-rubygem-json	Jun 9, 2026	May 9, 2026
Redhat_linux	—	Upgrade ruby-bundled-gemsUpgrade ruby-debuginfoUpgrade rubygem-abrtUpgrade ruby-libs-debuginfoUpgrade rubygem-mysql2Upgrade rubygem-mysql2-debugsourceUpgrade rubygem-openssl-debuginfoUpgrade rubygem-psychUpgrade rubygemsUpgrade rubygem-rbsUpgrade ruby4.0-debugsourceUpgrade ruby-libsUpgrade rubygem-did_you_meanNo solution existsUpgrade rubygem-jsonUpgrade rubygem-bsonUpgrade rubygem-net-telnetUpgrade rubygem-test-unitUpgrade rubygem-rbs-debuginfoUpgrade rubygem-bundler-docUpgrade rubygem-pg-debugsourceUpgrade ruby4.0-debuginfoUpgrade ruby4.0-rubygem-pgUpgrade rubyUpgrade rubygem-mongo-docUpgrade ruby-debugsourceUpgrade rubygem-abrt-docUpgrade rubygem-rssUpgrade rubygem-psych-debuginfoUpgrade rubygem-pgUpgrade ruby-docUpgrade ruby4.0-rubygem-pg-debuginfoUpgrade rubygem-racc-debuginfoUpgrade rubygem-rexmlUpgrade ruby-tcltkUpgrade rubygem-power_assertUpgrade rubygem-pg-debuginfoUpgrade rubygem-io-consoleUpgrade rubygem-bundlerUpgrade rubygem-opensslUpgrade rubygem-rdocUpgrade rubygem-pg-docUpgrade rubygem-bigdecimalUpgrade rubygem-xmlrpcUpgrade rubygem-mysql2-docUpgrade rubygem-bson-debuginfoUpgrade rubygem-bigdecimal-debuginfoUpgrade rubygem-raccUpgrade rubygem-bson-docUpgrade ruby4.0-rubygem-mysql2-debuginfoUpgrade ruby-irbUpgrade rubygem-json-debuginfoUpgrade rubygem-rakeUpgrade ruby4.0Upgrade ruby-bundled-gems-debuginfoUpgrade rubygem-mysql2-debuginfoUpgrade ruby4.0-docUpgrade rubygem-irbUpgrade ruby-default-gemsUpgrade ruby4.0-rubygem-mysql2Upgrade rubygem-bson-debugsourceUpgrade rubygem-mongoUpgrade ruby4.0-develUpgrade rubygem-minitestUpgrade rubygems-develUpgrade ruby-develUpgrade rubygem-io-console-debuginfoUpgrade rubygem-typeprof	Jul 2, 2026	May 9, 2026
Rocky_linux	—	Upgrade rubygem-json-debuginfoUpgrade rubygem-pg-debuginfoUpgrade rubygem-rbs-debuginfoUpgrade rubygem-openssl-debuginfoUpgrade ruby4.0-rubygem-pg-debuginfoUpgrade ruby4.0-rubygem-pgUpgrade ruby4.0-rubygem-mysql2Upgrade rubygem-bson-debuginfoUpgrade ruby4.0Upgrade ruby-debugsourceUpgrade rubygem-psychUpgrade ruby-libsUpgrade ruby4.0-rubygem-mysql2-debuginfoUpgrade ruby-debuginfoUpgrade rubygem-racc-debuginfoUpgrade rubygem-mysql2-debugsourceUpgrade rubygem-bigdecimalUpgrade rubygem-io-consoleUpgrade rubygem-mysql2Upgrade ruby-libs-debuginfoUpgrade ruby-bundled-gemsUpgrade ruby-develUpgrade ruby4.0-debugsourceUpgrade ruby-bundled-gems-debuginfoUpgrade rubygem-opensslUpgrade ruby4.0-develUpgrade rubygem-psych-debuginfoUpgrade rubygem-mysql2-debuginfoUpgrade rubygem-io-console-debuginfoUpgrade rubyUpgrade rubygem-pg-debugsourceUpgrade rubygem-bsonUpgrade rubygem-bigdecimal-debuginfoUpgrade ruby4.0-debuginfoUpgrade rubygem-jsonUpgrade rubygem-raccUpgrade rubygem-pgUpgrade rubygem-rbsUpgrade rubygem-bson-debugsource	Jul 3, 2026	Jul 1, 2026
Ubuntu	—	Upgrade ruby2.7 (Ubuntu Pro)Upgrade ruby2.5 (Ubuntu Pro)Upgrade libruby2.3 (Ubuntu Pro)Upgrade libruby3.3Upgrade libruby2.5 (Ubuntu Pro)Upgrade ruby3.2Upgrade ruby2.3 (Ubuntu Pro)Upgrade ruby3.3Upgrade libruby3.2Upgrade libruby2.7 (Ubuntu Pro)Upgrade ruby3.0Upgrade libruby3.0	Jun 16, 2026	Jun 15, 2026

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CVSS Details

Covered by Rapid7

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