CRLF Command Injection in Ruby's IMAP Client
CVE-2026-47240

5.8MEDIUM

Key Information:

Vendor

Ruby

Status
Net-imap
Vendor
CVE Published:
22 June 2026

What is CVE-2026-47240?

The Net::IMAP library in Ruby has a vulnerability that allows for potential CRLF command injection attacks. An attacker can exploit this weakness when using commands that accept raw data, particularly if the IMAP server does not support non-synchronizing literals. This may result in the injection of arbitrary IMAP commands, compromising the integrity of email operations like searching and fetching. Users are encouraged to update to versions 0.6.5 and 0.5.15 or higher to mitigate these risks.

Affected Version(s)

net-imap >= 0.6.0, < 0.6.4.1 < 0.6.0, 0.6.4.1

net-imap < 0.5.15 < 0.5.15

References

https://github.com/ruby/net-imap/security/advisories/GHSA...
x_refsource_CONFIRM

CVSS V4

Score:
5.8
Severity:
MEDIUM
Confidentiality:
None
Integrity:
High
Availability:
Low
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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