Vulnerability · Published Oct 9, 2026 · Assigned by VulnCheck

CVE-2026-108109PHPNuxBill through 2025.3.20 Account Takeover via Brute-Forceable Password Reset Code

Critical 9.1

In plain English

A critical-severity security flaw in phpnuxbill from hotspotbilling. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities).

Severity (CVSS 3.1)9.1Critical

Exploit odds (30 days)0.4%top 66.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

PHPNuxBill through 2025.3.20 contains an account takeover vulnerability in the customer password reset flow in system/controllers/forgot.php that allows unauthenticated attackers to brute-force the 6-digit otp_code. Attackers knowing a customer username can guess the code without attempt limits or lockout, then read the newly set password from the HTTP response to hijack the account.

Affected products (as reported)

Vendor	Product	Versions
hotspotbilling	phpnuxbill	0 – through 2025.3.20

Weakness: CWE-307 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References

GitHub Security Advisory (GHSA-337r-rrrc-r559) vendor-advisory
Patch Commit patch
https://github.com/hotspotbilling/phpnuxbill/blob/2025.3.13/system/controllers/forgot.php#L41 technical-description
https://github.com/hotspotbilling/phpnuxbill product
VulnCheck Advisory: PHPNuxBill through 2025.3.20 Account Takeover via Brute-Forceable Password Reset Code third-party-advisory