Bug 2560176 (CVE-2026-115775)

Summary:	CVE-2026-115775 twisted: twisted: Denial of Service via memory exhaustion in XML stream parser
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	dschmidt, eglynn, jjoyce, jlanda, jpretori, jschluet, jwong, kshier, lhh, mburns, mgarciac, omaciel, rbobbitt, simaishi, stcannon, yguenane
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in Twisted. An unauthenticated remote attacker can cause a Denial of Service (DoS) by exhausting server memory. The issue occurs because the XML stream parser retains unfinished elements in memory without enforcing size or element count limits. By transmitting a continuous stream of child elements within an unclosed container during pre-authentication communication, an attacker can crash the server process.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-10-23 20:31:33 UTC

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.10.0rc1, the twisted.words.xish.domish ExpatElementStream parser allows an unauthenticated remote peer to keep a container element open while continuously adding child elements. The parser retains the unfinished stanza as an in-memory tree without a byte or element-count limit, and XMPP pre-authentication stream parsing exposes this behavior before credentials are accepted. A single connection can therefore exhaust server memory and terminate the process. This issue is fixed in version 26.10.0rc1.