Bug 2496524

Summary:	CVE-2026-11946 open62541: open62541: Denial of Service via unvalidated endpoint URL length [fedora-all]
Product:	[Fedora] Fedora	Reporter:	Michalis Papadopoullos <mpapadop>
Component:	open62541	Assignee:	Jens Reimann <jreimann>
Status:	CLOSED ERRATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	medium	Docs Contact:
Priority:	unspecified
Version:	rawhide	CC:	jreimann, thofmann
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["98fcf907-f748-4f44-9b00-c219b726c8f9"]}
Fixed In Version:	open62541-1.5.6-1.fc44 open62541-1.5.6-1.fc43	Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2026-08-05 00:57:10 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Michalis Papadopoullos 2026-07-02 13:06:25 UTC

Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

An unauthenticated remote attacker can exhaust
server memory via the GetEndpoints Discovery Service in open62541. The
endpointUrl field of GetEndpointsRequest is not validated for length. An
attacker can declare an arbitrarily large string (up to ~4.09 GB via the UInt32
length field) delivered across intermediate chunks without ever sending the
final chunk. The server buffers all chunks in RAM indefinitely until the
SecureChannel times out. The attack is
pre-session and bypasses all encryption configurations.



The issue affects open62541: from 1.4.0 through 1.4.16, from 1.5.0 through 1.5.4, master.

Comment 1 Fedora Update System 2026-07-27 13:09:21 UTC

FEDORA-2026-23b21104ef (open62541-1.5.6-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-23b21104ef

Comment 2 Fedora Update System 2026-07-27 13:09:30 UTC

FEDORA-2026-1435f05fde (open62541-1.5.6-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-1435f05fde

Comment 3 Fedora Update System 2026-07-28 01:36:07 UTC

FEDORA-2026-23b21104ef has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-23b21104ef`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-23b21104ef

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 4 Fedora Update System 2026-07-28 01:57:46 UTC

FEDORA-2026-1435f05fde has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-1435f05fde`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-1435f05fde

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 5 Fedora Update System 2026-08-05 00:57:10 UTC

FEDORA-2026-23b21104ef (open62541-1.5.6-1.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 6 Fedora Update System 2026-08-05 01:10:48 UTC

FEDORA-2026-1435f05fde (open62541-1.5.6-1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.