CVE-2016-6559
The BSD libc library's link_ntoa() function may be vulnerable to a classic buffer overflow
- Published
- Updated
- Reserved
- Assigned by
- certcc
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.
Timeline
ID reserved
By certcc
- 24 months later
· 24 months later
Published
- 6 years later
· 6 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | Critical9.8 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 3.7% · top 10% of all CVEs (8 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
Affected products
- affected link_ntoa()
References (4)
- 1037398 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
- FreeBSD-SA-16:37 (opens in a new tab)vendor-advisoryx_refsource_FREEBSDx_transferred
- VU#548487 (opens in a new tab)third-party-advisoryx_refsource_CERT-VNx_transferred
- 94694 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2016-6559)Record last updated .