CVE-2026-42304

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/twisted/twisted/security/advisories/GHSA-grgv-6hw6-v9g4	Exploit Mitigation Vendor Advisory
https://github.com/twisted/twisted/security/advisories/GHSA-grgv-6hw6-v9g4	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:twisted:twisted::::::::
	cpe:2.3:a:twisted:twisted:26.4.0:rc1::::::

History

No history.

Information

Published : 2026-05-13 21:16

Updated : 2026-06-17 10:47

NVD link : CVE-2026-42304

Mitre link : CVE-2026-42304

CVE.ORG link : CVE-2026-42304

JSON object : View

Products Affected

twisted

twisted

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-407

Inefficient Algorithmic Complexity

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