CVSS 3.0
8.4 highCVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVE-2016-2856
High (8.4). EPSS 1.0% chance of exploitation in the next 30 days.
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.
Severity
- EPSS
- 1.0% chance of exploitation in the next 30 days; higher than 63% of CVEs (scores of 2026-10-31)
- CWE
- CWE-264
- Published
- Modified
- Record from
- the NVD, synced
Affected
- canonical:ubuntu_linux
- debian:debian_linux
References
- http://anonscm.debian.org/cgit/pkg-glibc/glibc.git/commit/?h=jessie&id=09f7764882a81e13e7b5d87d715412283a6ce403
- http://anonscm.debian.org/cgit/pkg-glibc/glibc.git/commit/?h=jessie&id=11475c083282c1582c4dd72eecfcb2b7d308c958
- http://people.canonical.com/~ubuntu-security/cve/2016/CVE-2016-2856.html
- http://www.halfdog.net/Security/2015/PtChownArbitraryPtsAccessViaUserNamespace/
- http://www.openwall.com/lists/oss-security/2016/02/23/3