CVE-2026-42256

Low

No strong exploitation signal.

CVSS base

6.5 MEDIUM

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

EPSS — probability of exploitation (30 days)

0.5%

41.7th percentile

CISA KEV

Not listed

Weakness / dates

CWE-770

Published 2026-05-09 · modified 2026-07-24

CVSS breakdown

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

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	N	None
User Interaction	R	Required
Scope	U	Unchanged
Confidentiality	N	None
Integrity	N	None
Availability	H	High

Timeline

2026-05-09 — Published (NVD)
2026-07-24 — Last modified (NVD)

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.

Affected

ruby-lang

References

Official: NVD · CVE.org