Vulnerability Monitor

The vendors, products, and vulnerabilities you care about

CVE-2016-6559

Improper bounds checking of the obuf variable in the link_ntoa() function in linkaddr.c of the BSD libc library may allow an attacker to read or write from memory. The full impact and severity depends on the method of exploit and how the library is used by applications. According to analysis by FreeBSD developers, it is very unlikely that applications exist that utilize link_ntoa() in an exploitable manner, and the CERT/CC is not aware of any proof of concept. A blog post describes the functionality of link_ntoa() and points out that none of the base utilities use this function in an exploitable manner. For more information, please see FreeBSD Security Advisory SA-16:37.

Security Impact Summary

This vulnerability carries a CRITICAL severity rating with a CVSS v3.1 score of 9.8, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts confidentiality (data exposure), integrity (unauthorized modifications), and availability (service disruption) for affected systems. Impacting 1 product from freebsd organizations running these solutions should prioritize assessment and patching.

Historical Context

First disclosed in 2018, this vulnerability was reported during a period defined by widespread IoT adoption challenges, mobile security concerns, and the emergence of advanced persistent threat (APT) techniques. Contemporary mitigation strategies focused on secure development practices and third-party component vetting.

Published

2018-07-13T20:29:00.910

Last Modified

2024-11-21T02:56:21.310

Status

Modified

Source

[email protected]

Severity

CVSSv3.0: 9.8 (CRITICAL)

CVSSv2 Vector

AV:N/AC:L/Au:N/C:P/I:P/A:P

Access Vector: NETWORK
Access Complexity: LOW
Authentication: NONE
Confidentiality Impact: PARTIAL
Integrity Impact: PARTIAL
Availability Impact: PARTIAL

Exploitability Score

10.0

Impact Score

6.4

Weaknesses

Type: Secondary
CWE-120
Type: Primary
CWE-119

Affected Vendors & Products

Type	Vendor	Product	Version/Range	Vulnerable?
Operating System	freebsd	freebsd	9.3	Yes
Operating System	freebsd	freebsd	10.1	Yes
Operating System	freebsd	freebsd	10.2	Yes
Operating System	freebsd	freebsd	10.3	Yes
Operating System	freebsd	freebsd	11.0	Yes

References

http://www.securitytracker.com/id/1037398 Third Party Advisory, VDB Entry ([email protected])
https://www.freebsd.org/security/advisories/FreeBSD-SA-16:37.libc.asc Vendor Advisory ([email protected])
https://www.kb.cert.org/vuls/id/548487 Third Party Advisory, US Government Resource ([email protected])
https://www.securityfocus.com/bid/94694 Third Party Advisory, VDB Entry ([email protected])
http://www.securitytracker.com/id/1037398 Third Party Advisory, VDB Entry (af854a3a-2127-422b-91ae-364da2661108)
https://www.freebsd.org/security/advisories/FreeBSD-SA-16:37.libc.asc Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://www.kb.cert.org/vuls/id/548487 Third Party Advisory, US Government Resource (af854a3a-2127-422b-91ae-364da2661108)
https://www.securityfocus.com/bid/94694 Third Party Advisory, VDB Entry (af854a3a-2127-422b-91ae-364da2661108)

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For freebsd's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.