CVE-2026-9303 Details
Description
A vulnerability was identified in calcom cal.diy up to 4.9.4. Impacted is an unknown function. The manipulation leads to cross-site request forgery. It is possible to initiate the attack remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.
A Cross-Site Request Forgery (CSRF) vulnerability has been identified in Cal.com versions through 4.9.4. This issue arises in the calendar availability API endpoint, which improperly processes incoming requests as 'text/plain' and lacks adequate CSRF protection. As a result, an attacker can remotely manipulate a user's calendar availability without their consent. The vulnerability is exacerbated by the application's cookie settings, which allow for cross-origin requests. Exploitation of this vulnerability could lead to unauthorized changes in a user's calendar data, causing potential disruptions in scheduled activities.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed May 23, 2026CISA-ADP
Assessed May 26, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://gist.github.com/YLChen-007/26663d9558e15994176dc420d2e11d48 | [email protected] | ExploitTechnical Description |
| https://gist.github.com/YLChen-007/dafada36e356bc895b09829d8ec57e49 | [email protected] | ExploitTechnical Description |
| https://vuldb.com/submit/812173 | [email protected] | Permission Required |
| https://vuldb.com/submit/812175 | [email protected] | Permission Required |
| https://vuldb.com/vuln/365250 | [email protected] | AdvisoryPermission Required |
| https://vuldb.com/vuln/365250/cti | [email protected] | AdvisoryPermission Required |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-352 | Cross-Site Request Forgery (CSRF) | [email protected] |
| CWE-862 | Missing Authorization | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| calcom cal.diy | <= v4.9.4 (semver) |
CPE
Remediation
| |
Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 23, 2026 | CVE Translated | [email protected] |
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| May 23, 2026 | New CVE Received | [email protected] |