CVE-2026-34576

Postiz: SSRF in upload-from-url endpoint allows fetching internal resources and cloud metadata

HIGH
7.7
CVSS Score
Published: April 2, 2026 at 05:23 PM UTC
Updated: July 24, 2026 at 09:20 PM UTC
2 products affected across 2 vendorsPostizPostiz

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Severity
HIGH7.7
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

Postiz is an AI social media scheduling tool. Prior to version 2.21.3, the POST /public/v1/upload-from-url endpoint accepts a user-supplied URL and fetches it server-side using axios.get() with no SSRF protections. The only validation is a file extension check (.png, .jpg, etc.) which is trivially bypassed by appending an image extension to any URL path. An authenticated API user can fetch internal network resources, cloud instance metadata, and other internal services, with the response data uploaded to storage and returned to the attacker. This issue has been patched in version 2.21.3.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2.21.3
Affected range stops below 2.21.3, so it looks safe — our inference, not a vendor statement
v < 2.21.3
Affected range stops below 2.21.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-89vp-m2qw-7v34
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.3

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-918

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