Paper/Archive/CVE-2025-71389

CVE-2025-71389

calcom cal.diy — Cal.com before 5.9.9 Remote Code Execution via RSC

CVSS 10.0 (CNA)10.0 / 10 × 3030.0 Not in CISA KEV+300.0 EPSS percentile 71.6.716 × 2014.3 No public exploit+100.0 SSVC exploitation: none+100.0

Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource

cal.diy< 5.9.95.9.9CNA

Scores by source

VulnCheck (CNA)10.0CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

VulnCheck (CNA)10.0CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

advisorygithub.com/calcom/cal.diy/security/advisories/GHSA-qjx2-5xqp-cpf4 patchgithub.com/calcom/cal.diy/pull/25592 refgithub.com/advisories/GHSA-9qr9-h5gf-34mp writeupvulncheck.com/advisories/cal-com-before-remote-code-execution-via-rsc