CVE-2026-34577
Postiz: Unauthenticated Full-Read SSRF via /public/stream Endpoint with Trivially Bypassable Extension Check
Description
Postiz is an AI social media scheduling tool. Prior to version 2.21.3, the GET /public/stream endpoint in PublicController accepts a user-supplied url query parameter and proxies the full HTTP response back to the caller. The only validation is url.endsWith('mp4'), which is trivially bypassable by appending .mp4 as a query parameter value or URL fragment. The endpoint requires no authentication and has no SSRF protections, allowing an unauthenticated attacker to read responses from internal services, cloud metadata endpoints, and other network-internal resources. This issue has been patched in version 2.21.3.
INFO
Published Date :
April 2, 2026, 6:16 p.m.
Last Modified :
July 24, 2026, 9:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE |
Solution
- Update Postiz to version 2.21.3.
- Verify SSRF protections are enabled.
- Review network access controls.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-34577.
| URL | Resource |
|---|---|
| https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.3 | Product Release Notes |
| https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-mv6h-v3jg-g539 | Exploit Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-34577 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-34577
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-34577 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-34577 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Jul. 24, 2026
Action Type Old Value New Value Added Translation Title: postiz-app de gitroomhq, Description: Postiz es una herramienta de programación de redes sociales con IA. Antes de la versión 2.21.3, el endpoint GET /public/stream en PublicController acepta un parámetro de consulta url proporcionado por el usuario y actúa como proxy de la respuesta HTTP completa al llamador. La única validación es url.endsWith('mp4'), lo cual es trivialmente eludible añadiendo .mp4 como valor de parámetro de consulta o fragmento de URL. El endpoint no requiere autenticación y no tiene protecciones SSRF, lo que permite a un atacante no autenticado leer respuestas de servicios internos, endpoints de metadatos en la nube y otros recursos internos de la red. Este problema ha sido parcheado en la versión 2.21.3. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'gitroomhq', 'product': 'postiz-app', 'versions': [{'status': 'affected', 'version': '< 2.21.3'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-34577', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-04-03T15:52:16.506297Z'} -
Initial Analysis by [email protected]
Apr. 07, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:gitroom:postiz:*:*:*:*:*:*:*:* versions up to (excluding) 2.21.3 Added Reference Type GitHub, Inc.: https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.3 Types: Product, Release Notes Added Reference Type GitHub, Inc.: https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-mv6h-v3jg-g539 Types: Exploit, Mitigation, Vendor Advisory -
New CVE Received by [email protected]
Apr. 02, 2026
Action Type Old Value New Value Added Description Postiz is an AI social media scheduling tool. Prior to version 2.21.3, the GET /public/stream endpoint in PublicController accepts a user-supplied url query parameter and proxies the full HTTP response back to the caller. The only validation is url.endsWith('mp4'), which is trivially bypassable by appending .mp4 as a query parameter value or URL fragment. The endpoint requires no authentication and has no SSRF protections, allowing an unauthenticated attacker to read responses from internal services, cloud metadata endpoints, and other network-internal resources. This issue has been patched in version 2.21.3. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N Added CWE CWE-918 Added Reference https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.3 Added Reference https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-mv6h-v3jg-g539