Summary
Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to perform system management tasks.
Security Fix(es):
* zlib: zlib: Memory corruption via buffer overflow in Zlib::GzipReader (CVE-2026-27820)
* net-imap: Net::IMAP: Arbitrary IMAP command injection via CRLF sequences in unvalidated input (CVE-2026-42257)
* ruby/net-imap: ruby: Net::IMAP: Denial of Service via large iteration count in SCRAM authentication (CVE-2026-42256)
* net-imap: Net::IMAP: Command injection via non-synchronizing literals (CVE-2026-47240)
* net-imap: Net::IMAP: Arbitrary IMAP command injection due to improper input validation (CVE-2026-47242)
* net-imap: rubygem-net-imap: Net::IMAP: Denial of Service via malformed command input (CVE-2026-47241)
Bug Fix(es) and Enhancement(s):
* ruby:4.0/ruby: Rebase to the latest Ruby 4.0 release [almalinux-9.8.z] (JIRA:AlmaLinux-211301)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Fixed packages 28
| Release | Package | Fixed in |
|---|---|---|
| AlmaLinux · 9 | ruby | 4.0.6-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | ruby-bundled-gems | 4.0.6-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | ruby-default-gems | 4.0.6-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | ruby-devel | 4.0.6-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | ruby-doc | 4.0.6-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | ruby-libs | 4.0.6-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-bigdecimal | 4.0.1-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-bundler | 4.0.16-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-io-console | 0.8.2-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-irb | 1.16.0-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-json | 2.18.0-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-minitest | 6.0.0-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-mysql2 | 0.5.7-1.module_el9.8.0+232+50f6dd36 |
| AlmaLinux · 9 | rubygem-mysql2-doc | 0.5.7-1.module_el9.8.0+232+50f6dd36 |
| AlmaLinux · 9 | rubygem-pg | 1.6.3-1.module_el9.8.0+232+50f6dd36 |
| AlmaLinux · 9 | rubygem-pg-doc | 1.6.3-1.module_el9.8.0+232+50f6dd36 |
| AlmaLinux · 9 | rubygem-power_assert | 3.0.1-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-psych | 5.3.1-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-racc | 1.8.1-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-rake | 13.3.1-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-rbs | 3.10.0-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-rdoc | 7.0.4-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-rexml | 3.4.4-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-rss | 0.3.2-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-test-unit | 3.7.5-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygem-typeprof | 0.31.1-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygems | 4.0.16-34.module_el9.8.0+289+5a070f48 |
| AlmaLinux · 9 | rubygems-devel | 4.0.16-34.module_el9.8.0+289+5a070f48 |
Vulnerabilities 6
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Medium 6.0
net-imap: Denial of service via high iteration count for `SCRAM-*` authentication
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 ser…
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Medium 5.8
net-imap: Command Injection via "raw" arguments to multiple commands
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, several Net::IMAP commands accept a raw string argument that is sent to the server without validation or escaping. If this …
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Medium 5.8
Net::IMAP: Command Injection via non-synchronizing literal in "raw" argument
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, several Net::IMAP commands accept a "raw data" argument that is sent verbatim after validation to prevent command injection. However, if a se…
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Medium 5.8
Net::IMAP: Command Injection via ID command argument
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, when Net::IMAP#id is called with a hash argument, although the ID field value strings are correctly quoted (escaping quoted specials), they w…
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Low 2.1
Net::IMAP: Denial of Service via incomplete raw argument validation
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, several Net::IMAP commands accept a raw string argument which is only validated to prevent CRLF injection and then sent verbatim. If this str…
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Low 1.7
zlib: Buffer Overflow in Zlib::GzipReader ungetc via large input leads to memory corruption
zlib is a Ruby interface for the zlib compression/decompression library. Versions 3.0.0 and below, 3.1.0, 3.1.1, 3.2.0 and 3.2.1 contain a buffer overflow vulnerability in the Zlib::GzipReader. The zstream_buffer_ungets function prepends caller-provided bytes…
References
-
report
https://access.redhat.com/security/cve/CVE-2026-27820
-
report
https://access.redhat.com/security/cve/CVE-2026-42256
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report
https://access.redhat.com/security/cve/CVE-2026-42257
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report
https://access.redhat.com/security/cve/CVE-2026-47240
-
report
https://access.redhat.com/security/cve/CVE-2026-47241
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report
https://access.redhat.com/security/cve/CVE-2026-47242
-
report
https://bugzilla.redhat.com/2459002
-
report
https://bugzilla.redhat.com/2468494
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report
https://bugzilla.redhat.com/2468500
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report
https://bugzilla.redhat.com/2491519
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report
https://bugzilla.redhat.com/2491523
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advisory
https://errata.almalinux.org/9/ALSA-2026-50827.html