Postiz has an unauthenticated billing-enforcement bypass via /public/modify-subscription
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-345.
Summary
Postiz is an AI social media scheduling tool. Versions prior to 2.21.8 contained an unauthenticated endpoint that accepted a signed token and applied subscription-enforcement side effects to the organization referenced in that token's claims, without verifying the token's intended purpose. The endpoint, /public/modify-subscription, could not change the persisted subscription tier, but it did execute enforcement-related side effects on the caller's own organization, including adjusting team-member enablement state, disabling integrations exceeding the asserted plan's limits, and resetting the scheduled-post cron when the asserted plan was the free tier. Impact is limited to the attacker's own organization and cannot be redirected at other tenants through this endpoint. This issue has been fixed in version 2.21.8.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA postiz-app (gitroomhq) Fixed in 2.21.8
Timeline
- 2026-10-02 Threatist record created from CVE-2026-48783
References
More gitroomhq vulnerabilities
- TI-2026-26825 Postiz: Unauthenticated Full-Read SSRF via /public/stream Endpoint with Trivially Bypassable Extension Check CVSS 3.1HIGH 8.6
- TI-2026-28982 Postiz has Server-Side Request Forgery via Redirect Bypass in /api/public/stream CVSS 3.1HIGH 8.2
- TI-2026-29238 Postiz Has Unrestricted File Upload via MIME Type Spoofing that Leads to Stored XSS CVSS 3.1CRITICAL 9.0
- TI-2026-26824 Postiz: SSRF in upload-from-url endpoint allows fetching internal resources and cloud metadata CVSS 4.0HIGH 8.3
- TI-2026-26837 Postiz: SSRF via Webhook Creation Endpoint Missing URL Safety Validation CVSS 3.1MEDIUM 5.4
- TI-2026-15715 Unauthenticated arbitrary file read via /uploads path traversal (URL-encoded separators) leading to instance takeover CVSS 4.0CRITICAL 9.3
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences