CVE-2026-42256

May 9, 2026, 8:16 p.m.

6.0
Medium

Description

Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. From versions 0.4.0 to before 0.4.24, 0.5.0 to before 0.5.14, and 0.6.0 to before 0.6.4, when authenticating a connection with SCRAM-SHA1 or SCRAM-SHA256, a hostile server can perform a computational denial-of-service attack on the client process by sending a big iteration count value. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.

Product(s) Impacted

Vendor Product Versions
Ruby
  • Net-imap
  • 0.4.0-0.4.24, 0.5.0-0.5.14, 0.6.0-0.6.4

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-770
Allocation of Resources Without Limits or Throttling
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a ruby net-imap 0.4.0-0.4.24 / / / / / / /
a ruby net-imap 0.5.0-0.5.14 / / / / / / /
a ruby net-imap 0.6.0-0.6.4 / / / / / / /

References

https://github.com/ruby/net-imap/commit/158d0b505074397cdb5ceb58935e42dd2bcfa612
https://github.com/ruby/net-imap/commit/808001bc45c06f7297a7e96d341279e041a7f7f4
https://github.com/ruby/net-imap/commit/99f59eab6064955a23debd95410263ad144df758
https://github.com/ruby/net-imap/releases/tag/v0.4.24
https://github.com/ruby/net-imap/releases/tag/v0.5.14
https://github.com/ruby/net-imap/releases/tag/v0.6.4
https://github.com/ruby/net-imap/security/advisories/GHSA-87pf-fpwv-p7m7

Tags

[email protected]
CWE-770
2026-05-09
CVE-2026-42256

CVSS Score

6.0 / 10

CVSS Data - 4.0

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Attack Requirements: PRESENT
  • Privileges Required: NONE
  • User Interaction: PASSIVE
  • Scope:
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: HIGH
  • Exploit Maturity: NOT_DEFINED

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

    View Vector String

Timeline

Published: May 9, 2026, 8:16 p.m.
Last Modified: May 9, 2026, 8:16 p.m.

Status : Received

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

[email protected]

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.