CVE-2026-9303 (GCVE-0-2026-9303)

Vulnerability from cvelistv5 – Published: 2026-05-23 13:30 – Updated: 2026-05-26 18:41
VLAI
Title
calcom cal.diy cross-site request forgery
Summary
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.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
4.3 (Medium)
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-352 - Cross-Site Request Forgery
  • CWE-862 - Missing Authorization
Assigner
References
Impacted products
Vendor Product Version
calcom cal.diy Affected: 4.9.0
Affected: 4.9.1
Affected: 4.9.2
Affected: 4.9.3
Affected: 4.9.4
    cpe:2.3:a:calcom:cal.diy:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Eric-z (VulDB User) VulDB CNA Team
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.