CVE-2026-115776

HIGH 7.5

Twisted: Unauthenticated Remote Denial of Service in the Twisted IRC Server via an Unbounded Line Buffer

CVSS Score

7.5

EPSS Score

0.0%

EPSS Percentile

0th

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.10.0rc1, twisted.words.protocols.irc.IRC.dataReceived retains all bytes received without a line feed in its per-connection buffer and applies no maximum line length. The twisted.words.service.IRCUser server subclass inherits this behavior, and buffering occurs before PASS, NICK, or USER authentication commands. An unauthenticated connection can continuously grow the buffer until the shared server process runs out of memory and drops all users. This issue is fixed in version 26.10.0rc1.

CWE	CWE-400 CWE-770
Vendor	twisted
Product	twisted
Published	Oct 23, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected Versions

twisted / twisted

< 26.10.0rc1

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/twisted/twisted/security/advisories/GHSA-53xc-49m8-p798 github.com: https://github.com/twisted/twisted/pull/12771 github.com: https://github.com/twisted/twisted/commit/01f8cff7753c1edac132380b2ea939fa6bdbab30 github.com: https://github.com/twisted/twisted/commit/ac90fb7b0ab73688a581fcd9a7c0577ec8ca3059 github.com: https://github.com/twisted/twisted/releases/tag/twisted-26.10.0rc1