CVE-2026-42246 (GCVE-0-2026-42246)
Vulnerability from cvelistv5 – Published: 2026-05-09 19:33 – Updated: 2026-05-12 02:29
VLAI?
Title
net-imap vulnerable to STARTTLS stripping via invalid response timing
Summary
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.
Severity ?
CWE
Assigner
References
8 references
| URL | Tags |
|---|---|
| https://github.com/ruby/net-imap/security/advisor… | x_refsource_CONFIRM |
| https://github.com/ruby/net-imap/commit/0ede4c40b… | x_refsource_MISC |
| https://github.com/ruby/net-imap/commit/24a4e770b… | x_refsource_MISC |
| https://github.com/ruby/net-imap/commit/97e2488fb… | x_refsource_MISC |
| https://github.com/ruby/net-imap/commit/f79d35bf5… | x_refsource_MISC |
| https://github.com/ruby/net-imap/releases/tag/v0.3.10 | x_refsource_MISC |
| https://github.com/ruby/net-imap/releases/tag/v0.4.24 | x_refsource_MISC |
| https://github.com/ruby/net-imap/releases/tag/v0.5.14 | x_refsource_MISC |
Impacted products
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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