PHPNuxBill through 2025.3.20 contains an authentication bypass vulnerability in RADIUS CHAP verification because Password::chap_verify() returns true when the supplied response does not match. Attackers who know a valid customer or PPPoE username can log in through MikroTik hotspot or PPPoE CHAP with any incorrect password to obtain network access and consume that customer's plan.
Attack Parameters
Attack Vector
Adjacent
Requires local network access
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
High
Complete data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
hotspotbilling:phpnuxbill
References 4
https://github.com/hotspotbilling/phpnuxbill
disclosure@vulncheck.com
https://github.com/hotspotbilling/phpnuxbill/blob/2025.3.13/system/autoload/Pas…
disclosure@vulncheck.com
https://github.com/hotspotbilling/phpnuxbill/security/advisories/GHSA-6f62-x25v…
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/phpnuxbill-through-2025.3.20-chap-authenti…
disclosure@vulncheck.com