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CVE-2026-42257

net-imap: Command Injection via "raw" arguments to multiple commands

Published: May 9, 2026Updated: Jul 24, 2026 Sources: CVE List NVDCWE-77
9.8CRITICAL
NVD MITRE
EPSS Score
0.4%
Top 64.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Workaround Only
Self-Check
OpenVAS

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-77CWE-93

Affected Products

ruby-lang
oss-projectaka ruby, rexml
net\LibraryLibrary
OSS Libraries / rubygems
ruby
oss-project·JP
net-imapLibrary
OSS Libraries / rubygems

Exploitability

Workaround Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Execution
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References

https://github.com/ruby/net-imap/releases/tag/v0.4.24
github.com
https://github.com/ruby/net-imap/releases/tag/v0.5.14
github.com
https://github.com/ruby/net-imap/releases/tag/v0.6.4
github.com
and 1 more references View all →

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