CVE-2026-42245

Name: CVE-2026-42245
Creator: NVD / NIST
Published: 2026-05-09T20:16:28.017+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

LOWCVSS 2.3/10EPSS 0.41%

Last modified Jun 17, 2026

CVE-2026-42245 is a low-severity vulnerability rated 2.3/10 on the CVSS scale. 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. EPSS estimates a 0.41% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS 4.0

2.3/10

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:L/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

EPSS Probability

0.41%

32.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-407

Affected Software

Vendor	Product	Versions	Update
Ruby-Lang	Net\	< 0.4.24	Imap
Ruby-Lang	Net\	>= 0.5.0, < 0.5.14	Imap
Ruby-Lang	Net\	>= 0.6.0, < 0.6.4	Imap

References

https://github.com/ruby/net-imap/commit/6091f7d6b1f3514cafbfe39c76f2b5d73de3ca96Patch
https://github.com/ruby/net-imap/commit/88d95231fc8afef11c1f074453f7d75b68c9dfdaPatch
https://github.com/ruby/net-imap/commit/de685f91a4a4cc75eb80da898c2bf8af08d34819Patch
https://github.com/ruby/net-imap/releases/tag/v0.4.24Release Notes
https://github.com/ruby/net-imap/releases/tag/v0.5.14Release Notes
https://github.com/ruby/net-imap/releases/tag/v0.6.4Release Notes
https://github.com/ruby/net-imap/security/advisories/GHSA-q2mw-fvj9-vvcwMitigation, Vendor Advisory

Timeline

Published: May 9, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-42245?

How severe is CVE-2026-42245?

CVE-2026-42245 has a CVSS score of 2.3/10 (LOW severity). The EPSS model estimates a 0.41% probability of exploitation in the next 30 days.

How do I fix CVE-2026-42245?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-42245?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST