CVE-2026-45573 Decidim: Push subscriptions can be abused for server-side requests
Authenticated users can trigger server-side requests to arbitrary HTTPS endpoints via unvalidated push subscriptions when VAPID delivery is enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45573?
CVE-2026-45573 is a medium-severity server-side request forgery vulnerability in decidim, published on 6 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Decidim is a participatory democracy framework. Prior to 0.30.9, from 0.31.0 before 0.31.5, and in 0.32.0.rc1 before 0.32.0.rc2, when VAPID delivery is enabled, the notification subscription flow stores a client-supplied push endpoint without validating that it belongs to an approved push service, and SendPushNotification later passes that endpoint to WebPush.payload_send, allowing an authenticated user to create stored, mostly blind server-side requests to arbitrary reachable HTTPS endpoints. This issue is fixed in versions 0.30.9, 0.31.5, and 0.32.0.rc2.
Weakness: CWE-918
Which versions are affected by CVE-2026-45573?
6 open source packages ship an affected version, including decidim-core.
| Package | Affected | Fixed in |
|---|---|---|
decidim-core RubyGems | All versions | 0.30.9 |
decidim-core RubyGems | All versions | 0.30.9 |
decidim-core RubyGems | From 0.31.0.rc1 | 0.31.5 |
decidim-core RubyGems | From 0.31.0.rc1 | 0.31.5 |
decidim-core RubyGems | From 0.32.0.rc1 | 0.32.0 |
decidim-core RubyGems | From 0.32.0.rc1 | 0.32.0 |
How do I fix CVE-2026-45573?
Upgrade decidim-core to a fixed version for your release line: 0.30.9, 0.31.5 or 0.32.0.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-45573 being exploited?
There is no known exploitation of CVE-2026-45573 in the wild and no public exploit code.
Sources
Also known as GHSA-2g9c-vf8h-prxx.