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CVE-2026-115774

CVE-2026-115774 · Twisted: Denial of Service in the Twisted IMAP4 Server via a Negative Literal Size in SEARCH

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.10.0rc1, twisted.mail.imap4.IMAP4Server reaches twisted.mail.imap4.parseNestedParens with a negative literal size in an authenticated SEARCH command after the client enters the selected mailbox state. The negative size moves the parser cursor below zero, and Python's negative indexing prevents the synchronous scanning loop from terminating. The loop freezes the single-threaded reactor, stopping other IMAP connections and any SMTP or POP3 services hosted in the same process until restart. This issue is fixed in version 26.10.0rc1.

CVSS 4.9 · Medium · Public exploit · Fix available

Published
Updated

Stack: python

Affected products and versions

  • twisted

    Versions
    • < 26.10.0rc1: Affected

    No fix published

  • twisted PyPI

    Versions
    • 1.0.1
    • 1.0.3
    • 1.0.4
    • 1.0.5
    • 1.0.6
    • 1.0.7
    • 1.1.0
    • 1.1.1
    • 1.2.0
    • 10.0.0
    • 10.1.0
    • 10.2.0
    • 11.0.0
    • 11.1.0
    • 12.0.0
    • 12.1.0
    • 12.2.0
    • 12.3.0
    • 13.0.0
    • 13.1.0
    • 13.2.0
    • 14.0.0
    • 14.0.1
    • 14.0.2
    • 15.0.0
    • 15.1.0
    • 15.2.0
    • 15.2.1
    • 15.3.0
    • 15.4.0
    • 15.5.0
    • 16.0.0
    • 16.1.0
    • 16.1.1
    • 16.2.0
    • 16.3.0
    • 16.3.1
    • 16.3.2
    • 16.4.0
    • 16.4.1
    • 16.5.0
    • 16.5.0rc1
    • 16.5.0rc2
    • 16.6.0
    • 16.6.0rc1
    • 16.7.0rc1
    • 16.7.0rc2
    • 17.1.0
    • 17.1.0rc1
    • 17.5.0
    • 17.9.0
    • 17.9.0rc1
    • 18.4.0
    • 18.4.0rc1
    • 18.7.0
    • 18.7.0rc1
    • 18.7.0rc2
    • 18.9.0
    • 18.9.0rc1
    • 19.10.0
    • 19.10.0rc1
    • 19.2.0
    • 19.2.0rc1
    • 19.2.0rc2
    • 19.2.1
    • 19.7.0
    • 19.7.0rc1
    • 2.1.0
    • 2.4.0
    • 2.5.0
    • 20.3.0
    • 20.3.0rc1
    • 21.2.0
    • 21.2.0rc1
    • 21.7.0
    • 21.7.0rc1
    • 21.7.0rc2
    • 21.7.0rc3
    • 22.1.0
    • 22.1.0rc1
    • 22.10.0
    • 22.10.0rc1
    • 22.2.0
    • 22.2.0rc1
    • 22.4.0
    • 22.4.0rc1
    • 22.8.0
    • 22.8.0rc1
    • 23.10.0
    • 23.10.0rc1
    • 23.8.0
    • 23.8.0rc1
    • 24.10.0
    • 24.10.0rc1
    • 24.11.0
    • 24.11.0rc1
    • 24.11.0rc2
    • 24.2.0rc1
    • 24.3.0
    • 24.7.0
    • 24.7.0rc1
    • 24.7.0rc2
    • 25.5.0
    • 25.5.0rc1
    • 26.4.0
    • 26.4.0rc2
    • 8.0.0
    • 8.0.1
    • 8.1.0
    • 8.2.0
    • 9.0.0
    Affected ranges
    • ECOSYSTEM: < 26.10.0rc1

    Update to 26.10.0rc1

Original sources

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