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.

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

CWE-400

CWE-405

CWE-409

CWE-770

CWE-789

CWE-1287

https://github.com/ruby/net-imap/commit/70e3ddd071a94e450b3238570af482c296380b35

https://github.com/ruby/net-imap/commit/c8c5a643739d2669f0c9a6bb9770d0c045fd74a3

https://github.com/ruby/net-imap/commit/cb92191b1ddce2d978d01b56a0883b6ecf0b1022

https://github.com/ruby/net-imap/security/advisories/GHSA-7fc5-f82f-cx69