Red Hat Security Advisory: ruby:2.5 security update
Affects Red Hat ruby:2.5Source GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 7.6 High · fixed in Red Hat package updates : patch Red Hat ruby:2.5 soon.
Data as of 6 Nov 2026, 02:03 UTC
- Patch
- Available – fixed in 0.6.4, 0.5.14, 0.4.24 +1
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 9 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade net-imap to 0.6.4, 0.5.14, 0.4.24 or 0.3.10.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| rubynet-imap | Affected
| Fixed in
|
| rubynet-imap | Affected
| Fixed in
|
| rubynet-imap | Affected
| Fixed in
|
| rubynet-imap | Affected
| Fixed in
|
AI-suggested
Red Hat has released updated Ruby 2.5 packages for Red Hat Enterprise Linux 8.4 that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:35866 and the referenced update article (https://access.redhat.com/articles/11258). No additional mitigation steps are indicated beyond applying the official patches.
Description
Two security vulnerabilities affecting Ruby's Net::IMAP library have been addressed in a Red Hat Enterprise Linux 8.4 update. The first is an IMAP command injection vulnerability via symbol arguments (CVE-2026-42258). The second is an information disclosure vulnerability that allows a man-in-the-middle attack to bypass TLS protections (CVE-2026-42246). These issues have been rated with an important security impact by Red Hat Product Security.
References
- access.redhat.com/errata/RHSA-2026:35866 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2468498 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2468499 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_35866.json (opens in a new tab)