CVE-2025-43857

Name
CVE-2025-43857
Description
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.5.7, 0.4.20, 0.3.9, and 0.2.5, there is a possibility for denial of service by memory exhaustion when net-imap reads server responses. At any time while the client is connected, a malicious server can send can send a "literal" byte count, which is automatically read by the client's receiver thread. The response reader immediately allocates memory for the number of bytes indicated by the server response. This should not be an issue when securely connecting to trusted IMAP servers that are well-behaved. It can affect insecure connections and buggy, untrusted, or compromised servers (for example, connecting to a user supplied hostname). This issue has been patched in versions 0.5.7, 0.4.20, 0.3.9, and 0.2.5.
NVD Severity
unknown
Other trackers
Mailing lists
Exploits
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
MISC https://github.com/ruby/net-imap/pull/442
MISC https://github.com/ruby/net-imap/pull/444/commits/0ae8576c1a90bcd9573f81bdad4b4b824642d105#diff-53721cb4d9c3fb86b95cc8476ca2df90968ad8c481645220c607034399151462
MISC https://github.com/ruby/net-imap/pull/445
MISC https://github.com/ruby/net-imap/pull/446
MISC https://github.com/ruby/net-imap/pull/447
CONFIRM https://github.com/ruby/net-imap/security/advisories/GHSA-j3g3-5qv5-52mj

Match rules

CPE URI Source package Min version Max version
net-imap >= 0.5.0 < 0.5.7
net-imap >= 0.4.0 < 0.4.20
net-imap >= 0.3.0 < 0.3.9
net-imap >= 0 < 0.2.5
cpe:2.3:a:ruby-lang:net\:\:imap:*:*:*:*:*:ruby:*:* net\ >= None < 0.2.5
cpe:2.3:a:ruby-lang:net\:\:imap:*:*:*:*:*:ruby:*:* net\ >= 0.3.0 < 0.3.9
cpe:2.3:a:ruby-lang:net\:\:imap:*:*:*:*:*:ruby:*:* net\ >= 0.4.0 < 0.4.20
cpe:2.3:a:ruby-lang:net\:\:imap:*:*:*:*:*:ruby:*:* net\ >= 0.5.0 < 0.5.7

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
ruby-net-imap 3.21-main 0.4.22-r0 Jakub Jirutka <jakub@jirutka.cz> fixed
ruby-net-imap 3.20-main 0.4.22-r0 Jakub Jirutka <jakub@jirutka.cz> fixed