# CVE-2026-48783: Postiz billing enforcement bypass in modify-subscription endpoint

Source: https://junglewise.ai/threats/cve-2026-48783-postiz-billing-enforcement-bypass-in-modify-subscription-endpoint  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-17. Updated: 2026-06-20  
License: CC BY 4.0 with a link back

CVE-2026-48783 · Severity: medium · CVSS 4.8 · Published 2026-06-17

Postiz is an AI-powered social media scheduling platform. A security flaw in its billing system allowed users to bypass subscription limits for their own accounts without making a payment. While an attacker could not affect other customers' data, they could gain unauthorized access to premium features like additional team members and integrations by sending specially crafted requests to an unprotected web address.

Technologies: [Gitroom Postiz](https://junglewise.ai/threats/technologies/postiz). Vendors: [Gitroom](https://junglewise.ai/threats/vendors/gitroom).

## Quick answers

**Is CVE-2026-48783 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-48783 being exploited in the wild.

**How severe is CVE-2026-48783?** Medium severity, with a CVSS score of 4.8, published 17 June 2026.

**Which products and versions are affected?** Gitroom Postiz < 2.21.8.

**Is there a fix for CVE-2026-48783?** A patch was published on 2026-05-22: Fix developed and released in version 2.21.8 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-48783 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-48783?** Check whether you run Gitroom Postiz at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A vulnerability exists in the /public/modify-subscription endpoint of Postiz due to insufficient verification of data authenticity (CWE-345) and missing authorization (CWE-862). The endpoint accepts a signed token and applies subscription-enforcement side effects based on the token's claims without verifying if the token was intended for that specific purpose. While the persisted subscription tier in the database remains unchanged, the application executes side effects such as enabling extra team members, enabling integrations, and resetting post-scheduling limits. This exploit requires Stripe to be configured on the instance and is limited to the attacker's own organization. The issue is fixed in version 2.21.8.

## Affected products

- gitroomhq postiz-app < 2.21.8

## Timeline

- 2026-05-22: disclosed: Advisory received and verified by Postiz team
- 2026-05-22: patched: Fix developed and released in version 2.21.8
- 2026-06-17: advisory: CVE-2026-48783 published

## References

- [https://gadvisory.org/advisories/PSA-2026-WWFR8X](https://gadvisory.org/advisories/PSA-2026-WWFR8X)
- [https://github.com/gitroomhq/postiz-app/commit/23696d2973510ae1f3f48bfa41a6bfbbf9827b05](https://github.com/gitroomhq/postiz-app/commit/23696d2973510ae1f3f48bfa41a6bfbbf9827b05)
- [https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.8](https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.8)
- [https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-v4wr-4j8g-4hfj](https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-v4wr-4j8g-4hfj)

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