5.3

CVE-2026-9303: calcom cal.diy Cross-Site Request Forgery (CSRF)

CVSS: 5.3v4.0MediumDeferred
Published 23-05-2026Last modified 26-05-2026
Open JSON

Vulnerability summary

CVE-2026-9303 is a medium (CVSS 5.3) Cross-Site Request Forgery (CSRF) vulnerability in calcom cal.diy. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.23%
0%100%
Low · +0.04 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Timeline

  1. 23-05-2026
    PublishedVulnerability first disclosed.
  2. 26-05-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

7 scores · 2 sources · 4 versions

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

13%

Versus all other CVEs

30-day change

+0.04 pp

From 0.19% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.23%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Dafada36E356Bc895B09829D8Ec57E49

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Calcom1 product
  • cal.diy4.9.0 | 4.9.1 | 4.9.2 | 4.9.3 | 4.9.4

1 vendor · 1 product

References

6 links