CVE-1999-0305

The system configuration control (sysctl) facility in BSD based operating systems OpenBSD 2.2 and earlier, and FreeBSD 2.2.5 and earlier, does not properly restrict source routed packets even when the (1) dosourceroute or (2) forwarding variables are set, which allows remote attackers to spoof TCP connections.

Published: 1998-02-01 Last update: 2026-04-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-1999-0305 is rated Moderate Risk (44.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.73%). 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-1999-0305

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 2025-03-30 0.81% 0.73% -0.08%
2 2025-03-29 0.73% 0.81% +0.08%
3 2025-03-17 — 0.73% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-1999-0305

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N 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:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-1999-0305

OS Trackers for CVE-1999-0305

vendor priority summary link
alpine — CVE-1999-0305: no source package rows; 0 state rows across 0 repos (none); fixed 0, open 0. https://security.alpinelinux.org/vuln/CVE-1999-0305

Affected software / configurations for CVE-1999-0305

Vendor Product Version Raw CPE
bsdi bsd_os — cpe:2.3:o:bsdi:bsd_os:*:*:*:*:*:*:*:*
freebsd freebsd 2.2 cpe:2.3:o:freebsd:freebsd:2.2:*:*:*:*:*:*:*
freebsd freebsd 2.2.5 cpe:2.3:o:freebsd:freebsd:2.2.5:*:*:*:*:*:*:*
openbsd openbsd 2.0 cpe:2.3:o:openbsd:openbsd:2.0:*:*:*:*:*:*:*
openbsd openbsd 2.1 cpe:2.3:o:openbsd:openbsd:2.1:*:*:*:*:*:*:*
openbsd openbsd 2.2 cpe:2.3:o:openbsd:openbsd:2.2:*:*:*:*:*:*:*

References for CVE-1999-0305

cvelogic Threat Intelligence