CVE-2026-54264 — @angular/service-worker
Fix: angular/angular@47d68dcCVE-2026-54264 is a Information Exposure vulnerability in @angular/service-worker. A fix is available for @angular/service-worker — see the affected versions and patch details below.
Angular: Sensitive Header Leakage on Cross-Origin Redirects in Angular Service Worker
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-54264.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@angular/service-workernpmDescription
An information disclosure vulnerability exists in the @angular/service-worker package of the Angular framework. When the Service Worker fetches assets, it preserves metadata (such as headers) from the original request. However, on cross-origin redirects, the Service Worker fails to strip sensitive headers, violating the Fetch redirect algorithm.
This allows a remote attacker to obtain sensitive credentials (e.g., Authorization tokens, Proxy-Authorization credentials, or session cookies) by triggering a cross-origin redirect to an untrusted external origin.
Impact
If an application configured with the Angular Service Worker fetches assets with credential headers (such as Authorization header), and one of those requests is redirected to a different origin, the Service Worker will forward those headers to the new origin. This exposes critical credentials and session identifiers to unauthorized third-party servers.
Attack Preconditions
For this vulnerability to be exploitable:
- Vulnerable Configuration: The application must utilize the
@angular/service-workerpackage to fetch assets. - Credentialed Requests: The application must attach sensitive request headers (like
Authorization,Proxy-Authorization, or rely on cookies) to asset-group requests. - Redirect Flow: These requests must encounter a cross-origin redirect to an attacker-controlled or untrusted domain.
Patched Versions
- 22.0.1
- 21.2.17
- 20.3.25
Credits
This vulnerability was discovered and reported by CodeMender from Google DeepMind.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @angular/service-worker | ≥ 22.0.0-next.0&&< 22.0.1 | 22.0.1npm install @angular/service-worker@22.0.1 |
| 📦npm | @angular/service-worker | ≥ 21.0.0-next.0&&< 21.2.17 | 21.2.17npm install @angular/service-worker@21.2.17 |
| 📦npm | @angular/service-worker | ≥ 20.0.0-next.0&&< 20.3.25 | 20.3.25npm install @angular/service-worker@20.3.25 |
| 📦npm | @angular/service-worker | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @angular/service-worker, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @angular/service-worker to 22.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-54264 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-54264 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-54264. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This Moderate information disclosure flaw in the Angular Service Worker could allow a remote attacker to obtain sensitive credentials by exploiting improper handling of cross-origin redirects. However, Red Hat JBoss Fuse is not affected by this vulnerability as the vulnerable code is not present in the product.
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.Source: Red Hat security advisory for CVE-2026-54264 (CC BY 4.0)
Frequently Asked Questions
Is CVE-2026-54264 in your dependencies?
O3 Security finds CVE-2026-54264 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.