CVE-2026-42346: CWE-918: Server-Side Request Forgery (SSRF) in gitroomhq postiz-app
Postiz is an AI social media scheduling tool. From version 2.16.6 to before version 2.21.7, all SSRF protections added in v2.21.4–v2.21.6 share a fundamental TOCTOU (Time-of-Check-Time-of-Use) vulnerability: isSafePublicHttpsUrl() resolves DNS to validate the target IP, but subsequent fetch() calls resolve DNS independently. An attacker controlling a DNS server can exploit this gap via DNS rebinding to redirect requests to internal network addresses. This issue has been patched in version 2.21.7.
AI Analysis
Technical Summary
The postiz-app from gitroomhq suffers from a SSRF vulnerability (CWE-918) due to a TOCTOU race condition in its SSRF protection mechanism. The function isSafePublicHttpsUrl() performs DNS resolution to validate target IPs, but the subsequent fetch() call performs a separate DNS resolution, enabling attackers controlling DNS to exploit DNS rebinding and redirect requests to internal network resources. Versions from 2.16.6 to before 2.21.7 are affected, and the vulnerability is fixed in version 2.21.7.
Potential Impact
Successful exploitation allows an unauthenticated attacker to cause the server to make HTTP requests to internal network addresses, potentially exposing sensitive internal resources or data. The CVSS score of 6.5 (medium severity) reflects high confidentiality impact, low integrity impact, and no availability impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade postiz-app to version 2.21.7 or later, where the TOCTOU SSRF vulnerability has been fixed. Since the vendor advisory does not provide additional remediation details, patch status is confirmed by the version update. No other mitigations are specified.
CVE-2026-42346: CWE-918: Server-Side Request Forgery (SSRF) in gitroomhq postiz-app
Description
Postiz is an AI social media scheduling tool. From version 2.16.6 to before version 2.21.7, all SSRF protections added in v2.21.4–v2.21.6 share a fundamental TOCTOU (Time-of-Check-Time-of-Use) vulnerability: isSafePublicHttpsUrl() resolves DNS to validate the target IP, but subsequent fetch() calls resolve DNS independently. An attacker controlling a DNS server can exploit this gap via DNS rebinding to redirect requests to internal network addresses. This issue has been patched in version 2.21.7.
CVSS v3.1
Score 6.5medium
Affected software
pkg:github/gitroomhq/postiz-appRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The postiz-app from gitroomhq suffers from a SSRF vulnerability (CWE-918) due to a TOCTOU race condition in its SSRF protection mechanism. The function isSafePublicHttpsUrl() performs DNS resolution to validate target IPs, but the subsequent fetch() call performs a separate DNS resolution, enabling attackers controlling DNS to exploit DNS rebinding and redirect requests to internal network resources. Versions from 2.16.6 to before 2.21.7 are affected, and the vulnerability is fixed in version 2.21.7.
Potential Impact
Successful exploitation allows an unauthenticated attacker to cause the server to make HTTP requests to internal network addresses, potentially exposing sensitive internal resources or data. The CVSS score of 6.5 (medium severity) reflects high confidentiality impact, low integrity impact, and no availability impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade postiz-app to version 2.21.7 or later, where the TOCTOU SSRF vulnerability has been fixed. Since the vendor advisory does not provide additional remediation details, patch status is confirmed by the version update. No other mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-26T13:26:14.515Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fe68edcbff5d861039d874
Added to database: 05/08/2026, 22:51:25 UTC
Last enriched: 05/16/2026, 10:55:41 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 109
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