Improper Authorization in Janeczku Calibre-Web Endpoint Functionality
CVE-2026-7709

5.3MEDIUM

Key Information:

Vendor

Janeczku

Status
Calibre-web
Vendor
CVE Published:
3 May 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-7709?

A significant vulnerability exists within the Janeczku Calibre-Web application, specifically in the Endpoint function located in the kobo_auth.py file. This flaw allows for unauthorized manipulation of the user_id argument in the generate_auth_token function, leading to improper authorization. Remote attackers can exploit this vulnerability, potentially gaining unauthorized access to user accounts. Despite attempts to inform the vendor, there has been no response regarding this issue. As the exploitation of this vulnerability is publicly accessible, it poses a serious risk to users of the affected versions.

Affected Version(s)

Calibre-Web 0.6.0

Calibre-Web 0.6.1

Calibre-Web 0.6.2

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-2026-7709 - Proof of Concept

References

https://vuldb.com/vuln/360885
vdb-entrytechnical-description
https://vuldb.com/vuln/360885/cti
signaturepermissions-required
https://vuldb.com/submit/805823
third-party-advisory

CVSS V4

Score:
5.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

JasperX (VulDB User)
VulDB CNA Team
.