Medium 5.4Published Apr 2, 2026

CVE-2026-34590Postiz: SSRF via Webhook Creation Endpoint Missing URL Safety Validation

Updated under an hour ago (Oct 27, 2026, 8:50 AM ET)

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Every CVE for gitroomhq postiz-app

Exploited in the last 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.

CVSS: 5.4 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Weakness (CWE): CWE-918
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Apr 3, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

gitroomhq postiz-app gitroomhq:postiz_app (from the name)	before 2.21.4	CNA record
gitroom postiz gitroom:postiz	before 2.21.4	NVD

References

References

https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-wc9c-7cv8-m225	x-refsource-confirm, exploit, mitigation, vendor-advisory
https://github.com/gitroomhq/postiz-app/commit/5ae4c950db6aa516a31454b7a45b9480bca40a11	x-refsource-misc, patch
https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.4	x-refsource-misc, product, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.