CVE-2026-106454: Twisted

Medium severity, CVSS 4.3. EPSS: 0.3% chance of exploitation in the next 30 days.

Twisted is an event-based framework for internet applications, supporting Python 3.6+. In 25.5.0 and earlier, wildcardToRegexp() in twisted/mail/imap4.py translates the IMAP asterisk and percent wildcards but passes all other characters from an authenticated client's LIST or LSUB pattern directly to re.compile(), allowing nested or otherwise expensive regular expression constructs to cause catastrophic backtracking when matched against mailbox names. Because Twisted uses a cooperative single-threaded reactor, the blocking match suspends all server input and output for the duration of the match. No fixed release is available as of this review.

Affected products

• Twisted Twisted: up to and including 25.5.0

Published 2026-10-06. Last modified 2026-10-07.