CVE-2026-42245

net-imap: Quadratic complexity when reading response literals

Published: May 9, 2026Updated: Jul 24, 2026 Sources: CVE List NVDCWE-407

7.5HIGH

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, Net::IMAP::ResponseReader has quadratic time complexity when reading large responses containing many string literals. A hostile server can send responses which are crafted to exhaust the client's CPU for a denial of service attack. 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

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-407

Affected Products

ruby-lang

oss-projectaka rexml, ruby

net\LibraryLibrary

OSS Libraries / rubygems

ruby

oss-project·JP

net-imapLibrary

OSS Libraries / rubygems

Exploitability

Official Patch Available

Workaround Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Impact

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References

https://github.com/ruby/net-imap/commit/6091f7d6b1f3514cafbfe39c76f2b5d73de3ca96

github.com

https://github.com/ruby/net-imap/commit/88d95231fc8afef11c1f074453f7d75b68c9dfda

github.com

https://github.com/ruby/net-imap/commit/de685f91a4a4cc75eb80da898c2bf8af08d34819

github.com

and 4 more references View all →

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