Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.4.0rc2, the twisted.names module is vulnerable to a Denial of Service (DoS) attack via resource exhaustion during DNS name decompression. A remote, unauthenticated attacker can exploit this by sending a crafted TCP DNS packet containing deeply chained compression pointers. This flaw bypasses previous loop-prevention logic, causing the single-threaded Twisted reactor to hang while processing millions of recursive lookups, effectively freezing the server. This vulnerability is fixed in 26.4.0rc2.

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Source ID Title
Github GHSA Github GHSA GHSA-grgv-6hw6-v9g4 Twisted has a Denial of Service (DoS) in twisted.names via Crafted DNS Compression Pointer Chains
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 19 May 2026 17:00:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:twisted:twisted:*:*:*:*:*:*:*:*
cpe:2.3:a:twisted:twisted:26.4.0:rc1:*:*:*:*:*:*

Thu, 14 May 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 13 May 2026 22:45:00 +0000

Type Values Removed Values Added
First Time appeared Twisted
Twisted twisted
Vendors & Products Twisted
Twisted twisted

Wed, 13 May 2026 20:30:00 +0000

Type Values Removed Values Added
Description Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.4.0rc2, the twisted.names module is vulnerable to a Denial of Service (DoS) attack via resource exhaustion during DNS name decompression. A remote, unauthenticated attacker can exploit this by sending a crafted TCP DNS packet containing deeply chained compression pointers. This flaw bypasses previous loop-prevention logic, causing the single-threaded Twisted reactor to hang while processing millions of recursive lookups, effectively freezing the server. This vulnerability is fixed in 26.4.0rc2.
Title Twisted: Denial of Service (DoS) in twisted.names via Crafted DNS Compression Pointer Chains
Weaknesses CWE-400
CWE-407
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-14T15:45:34.746Z

Reserved: 2026-04-26T12:13:55.552Z

Link: CVE-2026-42304

cve-icon Vulnrichment

Updated: 2026-05-14T15:45:21.220Z

cve-icon NVD

Status : Analyzed

Published: 2026-05-13T21:16:46.933

Modified: 2026-05-19T16:47:32.543

Link: CVE-2026-42304

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-13T22:30:05Z

Weaknesses