CVE-2003-1491

Kerio Personal Firewall (KPF) 2.1.4 has a default rule to accept incoming packets from DNS (UDP port 53), which allows remote attackers to bypass the firewall filters via packets with a source port of 53.

Published: 2003-12-31 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2003-1491 is rated Moderate Risk (60.6/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.37%). EPSS rose +2.10% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2003-1491

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.27% 2.37% +2.10%
2 2025-03-17 1.21% 0.27% -0.94%
3 2024-08-27 — 1.21% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2003-1491

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2003-1491

Affected software / configurations for CVE-2003-1491

Vendor Product Version Raw CPE
kerio personal_firewall 2.1.4 cpe:2.3:a:kerio:personal_firewall:2.1.4:*:*:*:*:*:*:*

References for CVE-2003-1491

cvelogic Threat Intelligence