HighFix available
ruby — security advisory
An issue was discovered in Ruby through 2.6.7, 2.7.x through 2.7.3, and 3.x through 3.0.1. Net::IMAP does not raise an exception when StartTLS fails with an an unknown response, which might allow man-in-the-middle attackers to bypass the TLS protections by leveraging a network position between the client and the registry to block the StartTLS command, aka a "StartTLS stripping attack."
- Products
- ruby
- Affected versions
- Not specified
- Fixed versions
- 2.6.8-r0, 2.7.4-r0
- CVEs
- CVE-2021-32066
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:04 UTC · Revision 1
Source evidence
An issue was discovered in Ruby through 2.6.7, 2.7.x through 2.7.3, and 3.x through 3.0.1. Net::IMAP does not raise an exception when StartTLS fails with an an unknown response, which might allow man-in-the-middle attackers to bypass the TLS protections by leveraging a network position between the client and the registry to block the StartTLS command, aka a "StartTLS stripping attack."
osv:ALPINE-CVE-2021-32066
ruby
Fixed versions: 2.6.8-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
ruby
Fixed versions: 2.7.4-r0
Complete source record
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"modified": "2026-10-23T17:17:56.187421875Z",
"provider": "osv",
"upstream": [
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"references": [
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},
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"source_id": "core-osv",
"document_id": 415440,
"published_at": "2021-08-01T19:15:07.697+00:00"
}