CVE-2016-2856
Description
pt_chown in the glibc package before 2.19-18+deb8u4 on Debian jessie; the elibc package before 2.15-0ubuntu10.14 on Ubuntu 12.04 LTS and before 2.19-0ubuntu6.8 on Ubuntu 14.04 LTS; and the glibc package before 2.21-0ubuntu4.2 on Ubuntu 15.10 and before 2.23-0ubuntu1 on Ubuntu 16.04 LTS and 16.10 lacks a namespace check associated with file-descriptor passing, which allows local users to capture keystrokes and spoof data, and possibly gain privileges, via pts read and write operations, related to debian/sysdeps/linux.mk. NOTE: this is not considered a vulnerability in the upstream GNU C Library because the upstream documentation has a clear security recommendation against the --enable-pt_chown option.
How to fix CVE-2016-2856
To remediate CVE-2016-2856, upgrade the affected package to a fixed version below.
- —upgrade to 2.21-1 or later
Is CVE-2016-2856 being exploited?
Low — EPSS is 0.7%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 2.21-1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.4 | CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |