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CVE-2026-108109

Status: DeferredCritical (9.3)—
Severity9.3Critical · CVSS 4.0
Exploitation probability0.39 %higher than 31% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

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.

CVSS

Base score
9.3
Version
4.0
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.39 %
Percentile among all scored CVEs
31
Score date
10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

AV:N sin autenticación permite ataque remoto a aplicación expuesta (T1190). Fuerza bruta de OTP sin límites facilita secuestro de cuenta (T1078.001) y cambio de credenciales (T1556.001) leyendo contraseña en respuesta HTTP.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

Vulnerability ScanningPrivileged Account ManagementPassword PoliciesNetwork SegmentationMulti-factor AuthenticationLimit Access to Resource Over Network

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Phpnuxbill — PhpnuxbillAI

CWEs

References

Show 6 references

Raw JSON (NVD)

Show
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    }
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  "sourceIdentifier": "disclosure@vulncheck.com"
}