Bug 2559067 - CVE-2026-103923 nextcloud: katex: Cross-site scripting via prototype pollution inheritance [epel-all]
Summary: CVE-2026-103923 nextcloud: katex: Cross-site scripting via prototype pollutio...
Keywords:
Status: ON_QA
Alias: None
Product: Fedora EPEL
Classification: Fedora
Component: nextcloud
Version: epel10
Hardware: Unspecified
OS: Unspecified
medium
medium
Target Milestone: ---
Assignee: Andrew Bauer
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard: {"flaws": ["d8a0e120-9cbc-4f4a-8b71-5...
Depends On:
Blocks: CVE-2026-103923
TreeView+ depends on / blocked
 
Reported: 2026-10-22 15:01 UTC by Vipul Nair
Modified: 2026-11-03 03:15 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Type: ---
Embargoed:


Attachments (Terms of Use)

Description Vipul Nair 2026-10-22 15:01:44 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.

KaTeX is a fast, easy-to-use JavaScript library for TeX math rendering on the web. From 0.11.0 until 0.18.2, KaTeX uses ordinary JavaScript property access for the renderer options object, the trust setting, default and processor setting metadata, and namespace lookup and group restoration, allowing inherited properties to be treated as explicitly supplied values. When Object.prototype is already polluted or an attacker controls the options object's prototype, attacker-controlled mathematical expressions can use an inherited trust value to enable trusted rendering and produce links capable of user-interaction cross-site scripting or loading attacker-selected external resources in a consuming application that inserts unsanitized KaTeX output into a page. KaTeX does not itself create the prototype pollution, and rendering an expression alone does not execute script. This issue is fixed in version 0.18.2.

Comment 1 Fedora Update System 2026-11-02 14:30:01 UTC
FEDORA-2026-72dc7f85d2 (nextcloud-35.0.2-1.fc45) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-72dc7f85d2

Comment 2 Fedora Update System 2026-11-02 14:31:35 UTC
FEDORA-2026-1ffca57dbf (nextcloud-35.0.2-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-1ffca57dbf

Comment 3 Fedora Update System 2026-11-02 14:31:50 UTC
FEDORA-2026-b6b68838b0 (nextcloud-35.0.2-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-b6b68838b0

Comment 4 Fedora Update System 2026-11-02 14:32:07 UTC
FEDORA-EPEL-2026-022ddd4a63 (nextcloud-35.0.2-1.el10_4) has been submitted as an update to Fedora EPEL 10.4.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-022ddd4a63

Comment 5 Fedora Update System 2026-11-02 14:32:19 UTC
FEDORA-EPEL-2026-573d684a29 (nextcloud-35.0.2-1.el10_3) has been submitted as an update to Fedora EPEL 10.3.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-573d684a29

Comment 6 Fedora Update System 2026-11-02 14:39:41 UTC
FEDORA-EPEL-2026-198200630f (nextcloud-35.0.2-1.el10_2) has been submitted as an update to Fedora EPEL 10.2.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-198200630f

Comment 7 Fedora Update System 2026-11-03 02:26:51 UTC
FEDORA-2026-72dc7f85d2 has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-72dc7f85d2`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-72dc7f85d2

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

Comment 8 Fedora Update System 2026-11-03 02:38:46 UTC
FEDORA-EPEL-2026-022ddd4a63 has been pushed to the Fedora EPEL 10.4 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-022ddd4a63

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

Comment 9 Fedora Update System 2026-11-03 02:53:42 UTC
FEDORA-EPEL-2026-573d684a29 has been pushed to the Fedora EPEL 10.3 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-573d684a29

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

Comment 10 Fedora Update System 2026-11-03 02:57:38 UTC
FEDORA-2026-1ffca57dbf 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-2026-1ffca57dbf`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-1ffca57dbf

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

Comment 11 Fedora Update System 2026-11-03 03:01:20 UTC
FEDORA-EPEL-2026-198200630f has been pushed to the Fedora EPEL 10.2 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-198200630f

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

Comment 12 Fedora Update System 2026-11-03 03:15:36 UTC
FEDORA-2026-b6b68838b0 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-b6b68838b0`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-b6b68838b0

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


Note You need to log in before you can comment on or make changes to this bug.