CVE-2025-71389
Cal.com before 5.9.9 Remote Code Execution via RSC
CVSS Score
10.0
EPSS Score
0.0%
EPSS Percentile
0th
Cal.com (calcom/cal.diy) before 5.9.9 is vulnerable to unauthenticated remote code execution because it bundles a version of Next.js whose React Server Components (RSC) request handling deserializes attacker-controlled input. A remote attacker can send a crafted RSC request to the server and cause arbitrary code to be executed during server-side processing, without authentication or user interaction. The flaw derives from the upstream Next.js vulnerability CVE-2025-55182 and is resolved in 5.9.9 by updating the affected dependency.
| CWE | CWE-94 |
| Vendor | calcom |
| Product | cal.diy |
| Published | Jul 23, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
calcom / cal.diy
0 < 5.9.9
References
github.com: https://github.com/calcom/cal.diy/security/advisories/GHSA-qjx2-5xqp-cpf4 github.com: https://github.com/calcom/cal.diy/pull/25592 github.com: https://github.com/advisories/GHSA-9qr9-h5gf-34mp vulncheck.com: https://www.vulncheck.com/advisories/cal-com-before-remote-code-execution-via-rsc