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TI-2025-18855 Aliases CVE-2025-25186GHSA-7fc5-f82f-cx69

Net::IMAP vulnerable to possible DoS by memory exhaustion

Priority MEDIUM 62CWE-1287Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 5 fixed, 6 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.

Summary

Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Starting in version 0.3.2 and prior to versions 0.3.8, 0.4.19, and 0.5.6, there is a possibility for denial of service by memory exhaustion in `net-imap`'s response parser. At any time while the client is connected, a malicious server can send can send highly compressed `uid-set` data which is automatically read by the client's receiver thread. The response parser uses `Range#to_a` to convert the `uid-set` data into arrays of integers, with no limitation on the expanded size of the ranges. Versions 0.3.8, 0.4.19, 0.5.6, and higher fix this issue. Additional details for proper configuration of fixed versions and backward compatibility are available in the GitHub Security Advisory.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00626 50th percentileScored 2026-11-07
Fix Partial net-imap (ruby): 0.3.8, 0.4.19, 0.5.6net-imap (RubyGems): 0.3.8, 0.4.19, 0.5.6Red Hat: 4 advisoriesRed Hat: 5 fixed, 6 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
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-imap0.3.2 to before 0.3.8; 0.4.0 to before 0.4.19; 0.5.0 to before 0.5.60.3.8, 0.4.19, 0.5.6Patch availableCNA
—net-imap (RubyGems)0.3.2 to before 0.3.80.3.8Patch availableGHSA-7fc5-f82f-cx69
—net-imap (RubyGems)0.4.0 to before 0.4.190.4.19Patch availableGHSA-7fc5-f82f-cx69
—net-imap (RubyGems)0.5.0 to before 0.5.60.5.6Patch availableGHSA-7fc5-f82f-cx69
  • net-imap Vendorruby Affected 0.3.2 to before 0.3.8; 0.4.0 to before 0.4.19; 0.5.0 to before 0.5.6 Fixed in 0.3.8, 0.4.19, 0.5.6 Patch available CNA
  • net-imap (RubyGems) Vendor— Affected 0.3.2 to before 0.3.8 Fixed in 0.3.8 Patch available GHSA-7fc5-f82f-cx69
  • net-imap (RubyGems) Vendor— Affected 0.4.0 to before 0.4.19 Fixed in 0.4.19 Patch available GHSA-7fc5-f82f-cx69
  • net-imap (RubyGems) Vendor— Affected 0.5.0 to before 0.5.6 Fixed in 0.5.6 Patch available GHSA-7fc5-f82f-cx69

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 0.3.8, 0.4.19, 0.5.6
  • Fix · GHSA-7fc5-f82f-cx69 net-imap (RubyGems) Fixed in 0.3.8 Advisory →
  • Fix · GHSA-7fc5-f82f-cx69 net-imap (RubyGems) Fixed in 0.4.19 Advisory →
  • Fix · GHSA-7fc5-f82f-cx69 net-imap (RubyGems) Fixed in 0.5.6 Advisory →

Red Hat 4 advisories

  • RHSA-2025:10217 Released 2025-07-02 · Red Hat rating Moderate
    ruby:3.3 security update
    • Red Hat Enterprise Linux AppStream (v. 8) ruby-3.3.8-4.module+el8.10.0+23024+a87ba659.aarch64::ruby:3.3, ruby-3.3.8-4.module+el8.10.0+23024+a87ba659.i686::ruby:3.3, ruby-3.3.8-4.module+el8.10.0+23024+a87ba659.ppc64le::ruby:3.3 +47
  • RHSA-2025:8131 Released 2025-05-26 · Red Hat rating Moderate
    ruby security update
    • Red Hat Enterprise Linux AppStream (v. 10) ruby-3.3.8-10.el10_0, ruby-bundled-gems-3.3.8-10.el10_0, ruby-default-gems-3.3.8-10.el10_0 +20
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) ruby-doc-3.3.8-10.el10_0
  • RHSA-2025:4493 Released 2025-05-06 · Red Hat rating Moderate
    ruby:3.3 security update
    • Red Hat Enterprise Linux AppStream (v. 9) ruby-3.3.8-4.module+el9.5.0+23030+26c9b8e1.aarch64::ruby:3.3, ruby-3.3.8-4.module+el9.5.0+23030+26c9b8e1.i686::ruby:3.3, ruby-3.3.8-4.module+el9.5.0+23030+26c9b8e1.ppc64le::ruby:3.3 +47
Show 1 more Red Hat advisories
  • RHSA-2025:3906 Released 2025-04-16 · Red Hat rating Important
    Logging for Red Hat OpenShift - 5.9.13
    • RHOL 5.9 for RHEL 9 openshift-logging/cluster-logging-operator-bundle, openshift-logging/cluster-logging-rhel9-operator, openshift-logging/eventrouter-rhel9 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat 3scale API Management Platform 2AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 9AffectedNo fix yet
RHOL 5.9 for RHEL 9Fixed RHSA-2025:3906
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:8131
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2025:10217
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:4493
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2025:8131
Not affected: 1 product
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-25186
  2. 2026-10-03 Alias added: GHSA-7fc5-f82f-cx69
  3. 2026-10-31 EPSS moved to the 50th–90th percentile

References

Advisory 1

Other 9

  • 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-2013-03637 Heap-based buffer overflow in Ruby 1.8, 1.9 before 1.9.3-p484, 2.0 before 2.0.0-p353, 2.1… CVSS 2.0MEDIUM 6.8
See all 135 →

Sources

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