Server-Side Request Forgery Vulnerability in Calcom Logo API
CVE-2026-9304

2.3LOW

Key Information:

Vendor

Calcom

Status
Cal.diy
Vendor
CVE Published:
23 May 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-9304?

A security flaw has been identified in Calcom's cal.diy product, specifically in the Logo API's function validateUrlForSSRF within the file apps/web/app/api/logo/route.ts. This vulnerability enables remote attackers to conduct server-side request forgery, potentially leading to unauthorized access to internal services. The complexity of the attack means that while exploitation is difficult, the details of the exploit have been released publicly, increasing the risk and capability for malicious actions. Efforts to inform the vendor prior to the public disclosure have gone unanswered.

Affected Version(s)

cal.diy 4.9.0

cal.diy 4.9.1

cal.diy 4.9.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-9304 - Proof of Concept

References

https://vuldb.com/vuln/365251
vdb-entrytechnical-description
https://vuldb.com/vuln/365251/cti
signaturepermissions-required
https://vuldb.com/submit/812176
third-party-advisory

CVSS V4

Score:
2.3
Severity:
LOW
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
High
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Eric-z (VulDB User)
VulDB CNA Team
.