Bug 2523529

Summary: CVE-2026-73422 python-jupytext: Astro: Arbitrary code execution via unescaped View Transition animation properties [fedora-all]
Product: [Fedora] Fedora Reporter: Joel Chamberlain <jochambe>
Component: python-jupytextAssignee: Jerry James <loganjerry>
Status: CLOSED ERRATA QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: loganjerry
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["6887c7e7-fe8c-4cf0-a347-116dd0478fb4"]}
Fixed In Version: python-jupytext-1.19.6-1.fc44 python-jupytext-1.19.6-1.fc43 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-10-14 01:23:41 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: 2514977    

Description Joel Chamberlain 2026-08-25 15:09:24 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.

Astro is a web framework for content-driven websites. From 2.9.0 until 7.1.0, Astro's server-side View Transition CSS generator interpolates animation properties into an inline style element without escaping them for CSS and HTML contexts. An attacker-controlled View Transition animation value such as duration can terminate the generated style element and inject arbitrary HTML or JavaScript. The affected code is packages/astro/src/runtime/server/transition.ts; renderTransition passes sheet.toString() into markHTMLString(), while addAnimationProperty serializes duration through toTimeValue() and also handles easing, direction, delay, fillMode, and name. Exploitation requires an on-demand or server-rendered route to pass attacker-controlled data into a View Transition animation definition and can execute arbitrary JavaScript in the affected application's origin, allowing access to sensitive page data and authenticated actions available to the victim. This issue is fixed in version 7.1.0.

Comment 1 Fedora Update System 2026-10-05 19:44:58 UTC
FEDORA-2026-3942ab86fd (python-jupytext-1.19.6-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-3942ab86fd

Comment 2 Fedora Update System 2026-10-06 01:24:02 UTC
FEDORA-2026-8b0bf60fcb 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-2026-8b0bf60fcb`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-8b0bf60fcb

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

Comment 3 Fedora Update System 2026-10-06 01:57:01 UTC
FEDORA-2026-620e232420 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-2026-620e232420`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-620e232420

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

Comment 4 Fedora Update System 2026-10-06 02:26:40 UTC
FEDORA-2026-3942ab86fd 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-2026-3942ab86fd`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-3942ab86fd

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

Comment 5 Fedora Update System 2026-10-14 01:23:41 UTC
FEDORA-2026-620e232420 (python-jupytext-1.19.6-1.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 2026-10-14 01:30:56 UTC
FEDORA-2026-3942ab86fd (python-jupytext-1.19.6-1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.