SSRF in Calcom Cal.diy
CVE-2026-9304
A security flaw has been discovered in calcom cal.diy up to 4.9.4. The affected element is the function validateUrlForSSRF of the file apps/web/app/api/logo/route.ts of the component Logo API. The manipulation results in server-side request forgery. It is possible to launch the attack remotely. Attacks of this nature are highly complex. The exploitability is described as difficult. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
Vulnerability class: SSRF (Server-Side Request Forgery)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.003 (22.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 22.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Calcom Cal.diy — versions 4.9.0, 4.9.1, 4.9.2
Weakness classification (CWE)
References
- vuldb.com/vuln/365251 (technical-description, vdb-entry)
- vuldb.com/vuln/365251/cti (signature, permissions-required)
- vuldb.com/submit/812176 (third-party-advisory)
- gist.github.com/YLChen-007/b3d0b85767b7e346a291933d602fbb3b (exploit)
Frequently asked questions
- What is CVE-2026-9304?
- CVE-2026-9304 is a medium-severity vulnerability in Calcom Cal.diy, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.0/10. Published 2026-05-23.
- How severe is CVE-2026-9304?
- Medium severity. CVSS v3 base score is 5.0 out of 10.