CVE-2026-42246
Last modified
CVE-2026-42246 is a high-severity vulnerability rated 7.6/10 on the CVSS scale. Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. EPSS estimates a 0.42% chance of exploitation in the next 30 days.
Description
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4.
Metrics
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Ruby-Lang | Net\ | < 0.3.10 | Imap |
| Ruby-Lang | Net\ | >= 0.4.0, < 0.4.24 | Imap |
| Ruby-Lang | Net\ | >= 0.5.0, < 0.5.14 | Imap |
| Ruby-Lang | Net\ | >= 0.6.0, < 0.6.4 | Imap |
References
- https://github.com/ruby/net-imap/security/advisories/GHSA-vcgp-9326-pqcpMitigation, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-42246?
How severe is CVE-2026-42246?
How do I fix CVE-2026-42246?
Are you affected by CVE-2026-42246?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST