Bug 2489685

Summary: CVE-2026-48779 jupyterlab: ws: Denial of Service via memory exhaustion from small WebSocket fragments [fedora-all]
Product: [Fedora] Fedora Reporter: Jon Moroney <jmoroney>
Component: jupyterlabAssignee: Lumír Balhar <lbalhar>
Status: CLOSED NOTABUG QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: lbalhar, python-packagers-sig, romain.geissler
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["0b7d7cff-5b53-4c6c-ba7b-2d048fde02ad"]}
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-06-17 10:17:54 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: 2489661    

Description Jon Moroney 2026-06-16 22:28:18 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.
Comment 1 Lumír Balhar 2026-06-17 10:17:54 UTC 
ws is explicitly declared as a webpack external in staging/webpack.config.js and is entirely absent from the browser-side static bundle (absent from third-party-licenses.json). JupyterLab's browser build uses the native WebSocket global; ws is a Node.js-only library used by @jupyterlab/services only in Node.js environments (tests/server-side), never bundled for the browser.