HIGH
CVE-2026-42246
CWE-392Published: May 9, 2026· Updated: May 13, 2026
7.6
CVSS v3.1
EPSS:0.05%probability of exploitation in 30 daysPercentile:15.5th
Official 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.
Technical Analysis
CVE-2026-42246 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation does not require any privileges, though user interaction (P) is needed, which slightly reduces the risk of mass automated attacks.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionP
ScopeX
Impact
Confidentiality
Integrity
Availability
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
Affected Vendors & Products
Mentioned vendors (from description):
Ruby
CPE data not yet available in NVD for this CVE.
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
All References (8)
Quick Facts
CVE IDCVE-2026-42246
CVSS Score7.6 / 10
SeverityHIGH
WeaknessCWE-392
CISA KEVNo
EPSS (30d)0.05%
PublishedMay 9, 2026
Related CVEs (CWE-392)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-42246 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.