CVE-2026-34590
MEDIUMPostiz: SSRF via Webhook Creation Endpoint Missing URL Safety Validation
Title source: cnaDescription
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.
Scores
CVSS v3
5.4
EPSS
0.0003
EPSS Percentile
10.0%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-918
Status
published
Products (2)
gitroom/postiz
< 2.21.4
gitroomhq/postiz-app
< 2.21.4
Published
Apr 02, 2026
Tracked Since
Apr 02, 2026