Vulnerability in Ruby Net-imap

CVE-2026-42245

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 st…

EPSS: 0.001 (24.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-42245?
CVE-2026-42245 is a high-severity vulnerability in Ruby Net-imap, classified under Inefficient Algorithmic Complexity. CVSS score: 7.5/10. Published 2026-05-09.
How severe is CVE-2026-42245?
High severity. CVSS v3 base score is 7.5 out of 10.