Bug 2526261

Summary: CVE-2026-48988 nextcloud: markdown-it: Denial of Service via quadratic processing of smartquotes with typographer enabled [fedora-all]
Product: [Fedora] Fedora Reporter: Marian Rehak <mrehak>
Component: nextcloudAssignee: Andrew Bauer <zonexpertconsulting>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: pampelmuse, zonexpertconsulting
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["71f48a1b-0719-4fd8-ad05-456e61498917"]}
Fixed In Version: nextcloud-34.0.4-1.fc45 nextcloud-34.0.4-1.el10_4 nextcloud-34.0.4-1.el10_2 nextcloud-34.0.4-1.el10_3 nextcloud-34.0.4-1.fc44 nextcloud-34.0.4-1.fc43 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-09-28 00:15:20 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:
Bug Depends On:    
Bug Blocks: 2490150    

Description Marian Rehak 2026-08-31 11:18:03 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.

markdown-it is a Markdown parser. Versions 14.1.1 and below contain a denial-of-service vulnerability when typographer: true is enabled, due to quadratic (O(n^2)) processing in the smartquotes rule. The issue stems from repeatedly modifying strings with replaceAt(), which performs O(n) slicing and concatenation per quote character. This can cause excessive CPU consumption when parsing quote-heavy, user-supplied markdown and may let attackers degrade or disrupt service availability. Although typographer is disabled by default, many production apps enable it for smart typography, making the issue relevant. This issue has been fixed in version 14.2.0.

Comment 1 Fedora Update System 2026-09-19 20:08:37 UTC
FEDORA-2026-5c1bbb46c3 (nextcloud-34.0.4-1.fc45) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-5c1bbb46c3

Comment 2 Fedora Update System 2026-09-19 20:09:10 UTC
FEDORA-2026-362f1943c8 (nextcloud-34.0.4-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-362f1943c8

Comment 3 Fedora Update System 2026-09-19 20:10:09 UTC
FEDORA-2026-c495e95154 (nextcloud-34.0.4-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-c495e95154

Comment 4 Fedora Update System 2026-09-19 20:10:49 UTC
FEDORA-EPEL-2026-9f20c01514 (nextcloud-34.0.4-1.el10_4) has been submitted as an update to Fedora EPEL 10.4.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-9f20c01514

Comment 5 Fedora Update System 2026-09-19 20:18:59 UTC
FEDORA-EPEL-2026-d1bff6d983 (nextcloud-34.0.4-1.el10_2) has been submitted as an update to Fedora EPEL 10.2.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-d1bff6d983

Comment 6 Fedora Update System 2026-09-19 20:18:59 UTC
FEDORA-EPEL-2026-31615b47ef (nextcloud-34.0.4-1.el10_3) has been submitted as an update to Fedora EPEL 10.3.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-31615b47ef

Comment 7 Fedora Update System 2026-09-20 01:41:46 UTC
FEDORA-2026-c495e95154 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-c495e95154`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-c495e95154

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

Comment 8 Fedora Update System 2026-09-20 01:47:40 UTC
FEDORA-EPEL-2026-9f20c01514 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-2026-9f20c01514

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

Comment 9 Fedora Update System 2026-09-20 02:01:56 UTC
FEDORA-2026-362f1943c8 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-2026-362f1943c8`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-362f1943c8

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

Comment 10 Fedora Update System 2026-09-20 02:02:37 UTC
FEDORA-EPEL-2026-d1bff6d983 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-d1bff6d983

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

Comment 11 Fedora Update System 2026-09-20 02:07:49 UTC
FEDORA-EPEL-2026-31615b47ef 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-2026-31615b47ef

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

Comment 12 Fedora Update System 2026-09-20 02:24:37 UTC
FEDORA-2026-5c1bbb46c3 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-2026-5c1bbb46c3`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-5c1bbb46c3

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

Comment 13 Fedora Update System 2026-09-28 00:15:20 UTC
FEDORA-2026-5c1bbb46c3 (nextcloud-34.0.4-1.fc45) has been pushed to the Fedora 45 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 14 Fedora Update System 2026-09-28 00:30:30 UTC
FEDORA-EPEL-2026-9f20c01514 (nextcloud-34.0.4-1.el10_4) has been pushed to the Fedora EPEL 10.4 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 15 Fedora Update System 2026-09-28 00:52:55 UTC
FEDORA-EPEL-2026-d1bff6d983 (nextcloud-34.0.4-1.el10_2) has been pushed to the Fedora EPEL 10.2 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 16 Fedora Update System 2026-09-28 01:11:13 UTC
FEDORA-EPEL-2026-31615b47ef (nextcloud-34.0.4-1.el10_3) has been pushed to the Fedora EPEL 10.3 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 17 Fedora Update System 2026-09-28 01:13:22 UTC
FEDORA-2026-362f1943c8 (nextcloud-34.0.4-1.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 18 Fedora Update System 2026-09-28 01:16:59 UTC
FEDORA-2026-c495e95154 (nextcloud-34.0.4-1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.