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TI-2026-34825 Aliases CVE-2026-47241GHSA-c4fp-cxrr-mj66

Net::IMAP: Denial of Service via incomplete raw argument validation

Priority LOW 17CWE-162Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Passive
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat.

Summary

Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, several Net::IMAP commands accept a raw string argument which is only validated to prevent CRLF injection and then sent verbatim. If this string is derived from user-controlled input, an attacker can force the next command to be absorbed as a continuation of the first command. This will cause the first command to eventually fail, but also prevents it from returning until another command is sent (from another thread). That other command will not return until the connection is closed. This vulnerability is fixed in 0.6.5 and 0.5.15.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00382 32nd percentileScored 2026-11-07
Fix Fixed net-imap (ruby): 0.6.4.1, 0.5.15net-imap (RubyGems): 0.6.4.1, 0.5.15Red Hat: 8 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
rubynet-imap0.6.0 to before 0.6.4.1; before 0.5.150.6.4.1, 0.5.15Patch availableCNA
—net-imap (RubyGems)0.6.0 to before 0.6.4.10.6.4.1Patch availableGHSA-c4fp-cxrr-mj66
—net-imap (RubyGems)before 0.5.150.5.15Patch availableGHSA-c4fp-cxrr-mj66
  • net-imap Vendorruby Affected 0.6.0 to before 0.6.4.1; before 0.5.15 Fixed in 0.6.4.1, 0.5.15 Patch available CNA
  • net-imap (RubyGems) Vendor— Affected 0.6.0 to before 0.6.4.1 Fixed in 0.6.4.1 Patch available GHSA-c4fp-cxrr-mj66
  • net-imap (RubyGems) Vendor— Affected before 0.5.15 Fixed in 0.5.15 Patch available GHSA-c4fp-cxrr-mj66

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:ruby-lang:net\:*:*:*:*:*:*:*:*——ruby
  • cpe:2.3:a:ruby-lang:net\:*:*:*:*:*:*:*:* Versions — — ·ruby

Remediation

  • Fix · CNA net-imap (ruby) Fixed in 0.6.4.1, 0.5.15
  • Fix · GHSA-c4fp-cxrr-mj66 net-imap (RubyGems) Fixed in 0.6.4.1 Advisory →
  • Fix · GHSA-c4fp-cxrr-mj66 net-imap (RubyGems) Fixed in 0.5.15 Advisory →

Red Hat 8 advisories

  • RHSA-2026:50827 Released 2026-08-05 · Red Hat rating Important
    ruby:4.0 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) ruby-4.0.6-34.module+el9.8.0+24564+e55418dc.aarch64::ruby:4.0, ruby-4.0.6-34.module+el9.8.0+24564+e55418dc.i686::ruby:4.0, ruby-4.0.6-34.module+el9.8.0+24564+e55418dc.ppc64le::ruby:4.0 +47
  • RHSA-2026:50828 Released 2026-08-05 · Red Hat rating Important
    ruby:3.3 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) ruby-3.3.12-8.module+el9.8.0+24568+2bbebe96.aarch64::ruby:3.3, ruby-3.3.12-8.module+el9.8.0+24568+2bbebe96.i686::ruby:3.3, ruby-3.3.12-8.module+el9.8.0+24568+2bbebe96.ppc64le::ruby:3.3 +47
  • RHSA-2026:50778 Released 2026-08-05 · Red Hat rating Important
    ruby security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) ruby-3.3.12-14.el10_2, ruby-bundled-gems-3.3.12-14.el10_2, ruby-default-gems-3.3.12-14.el10_2 +20
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) ruby-doc-3.3.12-14.el10_2
Show 5 more Red Hat advisories
  • RHSA-2026:50773 Released 2026-08-05 · Red Hat rating Important
    ruby4.0 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) ruby4.0-4.0.6-36.el10_2, ruby4.0-devel-4.0.6-36.el10_2, ruby4.0-rubygem-mysql2-0.5.7-36.el10_2 +1
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) ruby4.0-doc-4.0.6-36.el10_2
  • RHSA-2026:50728 Released 2026-08-05 · Red Hat rating Important
    ruby:3.3 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 8) ruby-3.3.12-8.module+el8.10.0+24567+c4e5368e.aarch64::ruby:3.3, ruby-3.3.12-8.module+el8.10.0+24567+c4e5368e.i686::ruby:3.3, ruby-3.3.12-8.module+el8.10.0+24567+c4e5368e.ppc64le::ruby:3.3 +47
  • RHSA-2026:40380 Released 2026-07-15 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images ruby3.3-3.3.10-23.4.hum1@aarch64, ruby3.3-3.3.10-23.4.hum1@src, ruby3.3-3.3.10-23.4.hum1@x86_64 +46
  • RHSA-2026:34293 Released 2026-07-01 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images ruby3.4-3.4.8-31.3.hum1@aarch64, ruby3.4-3.4.8-31.3.hum1@src, ruby3.4-3.4.8-31.3.hum1@x86_64 +46
  • RHSA-2026:33551 Released 2026-06-30 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images ruby4.0-4.0.0-33.4.hum1@aarch64, ruby4.0-4.0.0-33.4.hum1@src, ruby4.0-4.0.0-33.4.hum1@x86_64 +46

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:50773, RHSA-2026:50778
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:50728
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:50827, RHSA-2026:50828
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:50773, RHSA-2026:50778
Red Hat Hardened ImagesFixed RHSA-2026:33551, RHSA-2026:34293, RHSA-2026:40380
Not affected: 2 products
  • Red Hat 3scale API Management Platform 2
  • Red Hat Hardened Images

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-47241
  2. 2026-10-03 Alias added: GHSA-c4fp-cxrr-mj66
  3. 2026-11-06 Affected versions changed · Red Hat

References

Advisory 1

Other 5

  • TI-2026-71508 Integer overflow in GitLab allows code execution on the server KEVCVSS 3.1CRITICAL 10.0
  • TI-2026-50176 Use after free in ruby json CVSS 4.0HIGH 8.7
  • TI-2017-12709 Ruby before 2.4.3 allows Net::FTP command injection. CVSS 3.0HIGH 8.8
  • TI-2008-03501 Algorithmic complexity vulnerability in the WEBrick::HTTPUtils.split_header_value… CVSS 2.0HIGH 7.8
  • TI-2021-09891 In Ruby through 3.0 on Windows, a remote attacker can submit a crafted path when a Web… CVSS 3.1HIGH 7.5
  • TI-2025-18855 Net::IMAP vulnerable to possible DoS by memory exhaustion CVSS 3.1MEDIUM 6.5
See all 135 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences