CVE-2026-34590: Gitroom Postiz

Medium severity, CVSS 5.4. EPSS: 0.3% chance of exploitation in the next 30 days.

Postiz is an AI social media scheduling tool. Prior to version 2.21.4, the POST /webhooks/ endpoint for creating webhooks uses WebhooksDto which validates the url field with only @IsUrl() (format check), missing the @IsSafeWebhookUrl validator that blocks internal/private network addresses. The update (PUT /webhooks/) and test (POST /webhooks/send) endpoints correctly apply @IsSafeWebhookUrl. When a post is published, the orchestrator fetches the stored webhook URL without runtime validation, enabling blind SSRF against internal services. This issue has been patched in version 2.21.4.

Affected products

• Gitroom Postiz: before 2.21.4 (fixed in 2.21.4)

Published 2026-04-02. Last modified 2026-07-24.