gitroomhq postiz-app up to 2.21.3 Webhook /webhooks/ IsUrl url server-side request forgery

CVSS Meta Temp Score
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5.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in gitroomhq postiz-app up to 2.21.3. Impacted is the function IsUrl of the file /webhooks/ of the component Webhook Handler. Such manipulation of the argument url leads to server-side request forgery. This vulnerability is documented as CVE-2026-34590. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in gitroomhq postiz-app up to 2.21.3. It has been rated as critical. Affected by this issue is the function IsUrl of the file /webhooks/ of the component Webhook Handler. The manipulation of the argument url with an unknown input leads to a server-side request forgery vulnerability. Using CWE to declare the problem leads to CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-34590 since 03/30/2026. The exploitation is known to be easy. The attack may be launched remotely. Technical details are known, but there is no available exploit.

Upgrading to version 2.21.4 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 5ae4c950db6aa516a31454b7a45b9480bca40a11 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.7

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.4
CNA Vector (GitHub_M): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: postiz-app 2.21.4
Patch: 5ae4c950db6aa516a31454b7a45b9480bca40a11

Timelineinfo

03/30/2026 CVE reserved
04/02/2026 +3 days Advisory disclosed
04/02/2026 +0 days VulDB entry created
04/02/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-wc9c-7cv8-m225
Status: Confirmed

CVE: CVE-2026-34590 (🔒)
GCVE (CVE): GCVE-0-2026-34590
GCVE (VulDB): GCVE-100-354986

Entryinfo

Created: 04/02/2026 23:52
Changes: 04/02/2026 23:52 (71)
Complete: 🔍
Cache ID: 216::103

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