CVE-2026-42245

HIGH

7.5

CVSS v3

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.

CWE-407

How to fix

Remediation Available

rubyRocky

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

rubyRed Hat / RHEL

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

ruby-bundled-gemsRocky

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-bundled-gemsRed Hat / RHEL

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-bundled-gems-debuginfoRocky

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-bundled-gems-debuginfoRed Hat / RHEL

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

ruby-debuginfoRocky

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

ruby-debuginfoRed Hat / RHEL

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-debugsourceRocky

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-debugsourceRed Hat / RHEL

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-default-gemsRed Hat / RHEL

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-7.module+el9.4.0+24474+8fc4d0bd.noarch::ruby:3.3RHSA-2026:36099

Fixed in:0:3.3.10-7.module+el8.10.0+24407+4a33a056.noarch::ruby:3.3RHSA-2026:33515

Fixed in:0:3.3.10-6.module+el9.6.0+24475+76cce029.noarch::ruby:3.3RHSA-2026:37238

Fixed in:0:4.0.3-33.module+el9.8.0+24428+77f1d00a.noarch::ruby:4.0RHSA-2026:33577

Fixed in:0:3.3.10-7.module+el9.8.0+24406+8975e57f.noarch::ruby:3.3RHSA-2026:33576

ruby-default-gemsRocky

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-6.module+el9.6.0+24475+76cce029.noarch::ruby:3.3RHSA-2026:37238

Fixed in:0:4.0.3-33.module+el9.8.0+24428+77f1d00a.noarch::ruby:4.0RHSA-2026:33577

Fixed in:0:3.3.10-7.module+el8.10.0+24407+4a33a056.noarch::ruby:3.3RHSA-2026:33515

Fixed in:0:3.3.10-7.module+el9.8.0+24406+8975e57f.noarch::ruby:3.3RHSA-2026:33576

Fixed in:0:3.3.10-7.module+el9.4.0+24474+8fc4d0bd.noarch::ruby:3.3RHSA-2026:36099

ruby-develRed Hat / RHEL

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-develRocky

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-docRocky

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:4.0.3-33.module+el9.8.0+24428+77f1d00a.noarch::ruby:4.0RHSA-2026:33577

Fixed in:0:3.3.10-6.module+el9.6.0+24475+76cce029.noarch::ruby:3.3RHSA-2026:37238

Fixed in:0:3.3.10-7.module+el9.8.0+24406+8975e57f.noarch::ruby:3.3RHSA-2026:33576

Fixed in:0:3.3.10-7.module+el8.10.0+24407+4a33a056.noarch::ruby:3.3RHSA-2026:33515

Fixed in:0:3.3.10-7.module+el9.4.0+24474+8fc4d0bd.noarch::ruby:3.3RHSA-2026:36099

ruby-docRed Hat / RHEL

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-6.module+el9.6.0+24475+76cce029.noarch::ruby:3.3RHSA-2026:37238

Fixed in:0:3.3.10-7.module+el9.4.0+24474+8fc4d0bd.noarch::ruby:3.3RHSA-2026:36099

Fixed in:0:3.3.10-7.module+el9.8.0+24406+8975e57f.noarch::ruby:3.3RHSA-2026:33576

Fixed in:0:3.3.10-7.module+el8.10.0+24407+4a33a056.noarch::ruby:3.3RHSA-2026:33515

Fixed in:0:4.0.3-33.module+el9.8.0+24428+77f1d00a.noarch::ruby:4.0RHSA-2026:33577

ruby-libsRed Hat / RHEL

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-libsRocky

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby-libs-debuginfoRed Hat / RHEL

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

ruby-libs-debuginfoRocky

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

Fixed in:0:3.3.10-13.el10_2RHSA-2026:33565

Fixed in:0:3.3.10-11.el10_0.2RHSA-2026:35895

ruby3Rocky

Fixed in:4-main@noarchRHSA-2026:38694

Fixed in:3-main@noarchRHSA-2026:33721

Fixed in:3-main@x86_64RHSA-2026:33721

Fixed in:4-main@noarchRHSA-2026:33552

Fixed in:4-main@srcRHSA-2026:33552

Fixed in:4-main@x86_64RHSA-2026:33552

Fixed in:3-main@aarch64RHSA-2026:33721

Fixed in:3-main@srcRHSA-2026:33721

ruby3Red Hat / RHEL

Fixed in:3-main@x86_64RHSA-2026:33721

Fixed in:4-main@noarchRHSA-2026:33552

Fixed in:4-main@srcRHSA-2026:33552

Fixed in:3-main@noarchRHSA-2026:33721

Fixed in:3-main@aarch64RHSA-2026:33721

Fixed in:4-main@aarch64RHSA-2026:33552

Fixed in:3-main@srcRHSA-2026:33721

Fixed in:4-main@x86_64RHSA-2026:33552

ruby4Rocky

Fixed in:0-main@srcRHSA-2026:33551

Fixed in:0-main@noarchRHSA-2026:33551

Fixed in:0-main@x86_64RHSA-2026:33551

Fixed in:0-main@aarch64RHSA-2026:33551

ruby4Red Hat / RHEL

Fixed in:0-main@x86_64RHSA-2026:33551

Fixed in:0-main@noarchRHSA-2026:33551

Fixed in:0-main@srcRHSA-2026:33551

Fixed in:0-main@aarch64RHSA-2026:33551

ruby4.0Rocky

Fixed in:0:4.0.3-35.el10_2RHSA-2026:33540

ruby4.0Red Hat / RHEL

Fixed in:0:4.0.3-35.el10_2RHSA-2026:33540

ruby4.0-debuginfoRed Hat / RHEL

Fixed in:0:4.0.3-35.el10_2RHSA-2026:33540

ruby4.0-debuginfoRocky

Fixed in:0:4.0.3-35.el10_2RHSA-2026:33540

ruby4.0-debugsourceRocky

Fixed in:0:4.0.3-35.el10_2RHSA-2026:33540

ruby4.0-debugsourceRed Hat / RHEL

Fixed in:0:4.0.3-35.el10_2RHSA-2026:33540

This vulnerability affects an unusually large number of packages. The highest-confidence fixes are shown above; the full list is longer. Check the referenced advisories for complete coverage.

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityHigh

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

Exploit Intelligence

0.41%probability of exploitation in 30 days

34thpercentile

Low risk: more likely to be exploited than 34% of all known CVEs.

References

Patch3

Vendor Advisory1

github.com

Release Notes3

Related Vulnerabilities

Other CWE-407 vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2020-27223	Medium	5.2	78%	-	Fix
CVE-2022-36021	Medium	5.5	60%	-	Fix
CVE-2021-33582	High	7.5	3.1%	-	Fix
CVE-2024-43485	High	7.5	3.1%	-	Fix
CVE-2024-43484	High	7.5	2.9%	-	Fix
CVE-2016-10396	High	7.5	2.9%	-	-

Common questions

How do I fix CVE-2026-42245?

Published advisories record a fix for 110 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2026-42245 being actively exploited?

Not that we know of. CVE-2026-42245 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.41% is the estimated probability that it will be exploited in the next 30 days. That is higher than 34% of all scored CVEs.

How severe is CVE-2026-42245?

CVE-2026-42245 has a CVSS v3 base score of 7.5, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2026-42245 affect?

Published advisories record a fix for ruby (Rocky), ruby (Red Hat / RHEL), ruby-bundled-gems (Rocky), ruby-bundled-gems (Red Hat / RHEL), and 106 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2026-42245

Markdown

[![CVE-2026-42245](https://tridentstack.com/cve/badge/CVE-2026-42245.svg)](https://tridentstack.com/cve/CVE-2026-42245)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-42245"><img src="https://tridentstack.com/cve/badge/CVE-2026-42245.svg" alt="CVE-2026-42245"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

See how it works Start freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-07-24.