Postiz has Multiple SSRF Vectors - Webhooks, RSS Feed, URL Loader

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

7.8 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:H/SI:L/SA:N · score source

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Summary Postiz has multiple SSRF vulnerabilities where user-provided URLs are fetched server-side without any IP validation or SSRF protection. Vulnerable Code 1. Webhook Send Endpoint (Most Critical) apps/backend/src/api/routes/webhooks.controller.ts lines 58-70: Accepts arbitrary URL via query parameter and fetches directly. 2. Stored Webhook Delivery apps/orchestrator/src/activities/post.activity.ts lines 256-281: 3. RSS/XML Feed Parser libraries/nestjs-libraries/src/database/prisma/autopost/autopost.service.ts line 135: 4. HTML Content Loader libraries/nestjs-libraries/src/database/prisma/autopost/autopost.service.ts line 185: Missing Protections - No request-filtering-agent or SSRF library - No private IP range filtering - No cloud metadata endpoint blocking - No DNS rebinding protection - URL validation only via @IsUrl() decorator (format only, no IP check) Attack Scenarios 1. POST /webhooks/send?url=http://169.254.169.254/latest/meta-data/ → AWS metadata theft 2. POST…

Published by the source

27 Mar 2026, 15:47 UTC

Last modified by the source

22 Apr 2026, 15:24 UTC

Source last checked

26 Oct 2026, 12:48 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-89v5-38xr-9m4j

2. Revision 2 · amended · 24 Oct 2026

   Reviewed OSV alias/range/CVSS4 correction; package source scopes and original publication preserved. No customer finding resolved.

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-89v5-38xr-9m4j

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: GHSA-89v5-38xr-9m4j

Advisory: Postiz has Multiple SSRF Vectors - Webhooks, RSS Feed, URL Loader
IDs: GHSA-89v5-38xr-9m4j
Record: https://patchnext.com/advisories/ghsa-89v5-38xr-9m4j (revision 3, source checked 26 Oct 2026, 12:48 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm postiz: affected <= 2.0.12

## Suggested inspection (read-only)
- `npm ls postiz --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on postiz.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-89v5-38xr-9m4j (OSV record GHSA-89v5-38xr-9m4j lists affected ranges: npm postiz >=0 <=2.0.12)
- Verified: https://github.com/advisories/GHSA-89v5-38xr-9m4j (GitHub-reviewed advisory GHSA-89v5-38xr-9m4j lists affected ranges: npm postiz >=0 <=2.0.12)

Commands are suggestions: review each one before running it.