Critical severity · published Jul 13, 2018
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
9.8
CVSS
3.7%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.7% · higher than 90% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
Freebsd · Freebsd
9.3; 10.1; 10.2; 10.3; 11.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2016-6559
CVE.org
https://www.cve.org/CVERecord?id=CVE-2016-6559
Third Party Advisory
http://www.securitytracker.com/id/1037398
Vendor Advisory
https://www.freebsd.org/security/advisories/FreeBSD-SA-16:37.libc.asc
Third Party Advisory
https://www.kb.cert.org/vuls/id/548487
Third Party Advisory
https://www.securityfocus.com/bid/94694
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