Denial of service via trailing literal marker
Published Jun 22, 2026 · Updated Jun 22, 2026
Denial of service in Ruby net-imap before 0.5.15 and 0.6.0 through 0.6.4 allows remote authenticated users to hang IMAP commands. Net::IMAP::RawData uses an incorrect trailing-marker regular expression, allowing criteria or attr strings ending in {0} or {0+} to be sent verbatim and absorb the next command. Exploitation requires user-controlled input to reach an affected command; the resulting command or concurrent thread hangs until the connection closes.
Summary
What happened
Denial of service in Ruby net-imap before 0.5.15 and 0.6.0 through 0.6.4 allows remote authenticated users to hang IMAP commands. Net::IMAP::RawData uses an incorrect trailing-marker regular expression, allowing criteria or attr strings ending in {0} or {0+} to be sent verbatim and absorb the next command. Exploitation requires user-controlled input to reach an affected command; the resulting command or concurrent thread hangs until the connection closes.
The record
- CVE
- CVE-2026-47241
- Published
- Jun 22, 2026
- Updated
- Jun 22, 2026
- Vendor
- libwww-perl
- Product
- net-imap
- Classifications
- CWE-162, CWE-182, CWE-186, T1499
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 22, 2026CVE publishedPublication date reported by the CVE source.
- Jun 22, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 0.5.15
- Affected versionversion=>= 0.6.0, < 0.6.4.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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