CVE-2016-2856

Published on: 03/13/2016 12:00:00 AM UTC

Last Modified on: 03/23/2021 11:27:16 PM UTC

CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Certain versions of Ubuntu Linux from Canonical contain the following vulnerability:

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.

  • CVE-2016-2856 has been assigned by [email protected] to track the vulnerability - currently rated as HIGH severity.

CVSS3 Score: 8.4 - HIGH

Attack
Vector
Attack
Complexity
Privileges
Required
User
Interaction
LOCAL LOW NONE NONE
Scope Confidentiality
Impact
Integrity
Impact
Availability
Impact
UNCHANGED HIGH HIGH HIGH

CVSS2 Score: 7.2 - HIGH

Access
Vector
Access
Complexity
Authentication
LOCAL LOW NONE
Confidentiality
Impact
Integrity
Impact
Availability
Impact
COMPLETE COMPLETE COMPLETE

CVE References

Description Tags Link
oss-security - Re: Access to /dev/pts devices via pt_chown and user namespaces www.openwall.com
text/html
URL Logo MLIST [oss-security] 20160306 Re: Access to /dev/pts devices via pt_chown and user namespaces
CVE-2016-2856 in Ubuntu people.canonical.com
text/html
URL Logo CONFIRM people.canonical.com/~ubuntu-security/cve/2016/CVE-2016-2856.html
USN-2985-2: GNU C Library regression | Ubuntu www.ubuntu.com
text/html
URL Logo UBUNTU USN-2985-2
404 Not Found anonscm.debian.org
text/html
Inactive LinkNot Archived
URL Logo CONFIRM anonscm.debian.org/cgit/pkg-glibc/glibc.git/commit/?h=jessie&id=09f7764882a81e13e7b5d87d715412283a6ce403
404 Not Found anonscm.debian.org
text/html
Inactive LinkNot Archived
URL Logo CONFIRM anonscm.debian.org/cgit/pkg-glibc/glibc.git/commit/?h=jessie&id=11475c083282c1582c4dd72eecfcb2b7d308c958
GNU glibc 'pt_chown' Local Security Bypass Vulnerability cve.report (archive)
text/html
URL Logo BID 84601
pt_chown Arbitrary Pts Device Access via User Namespaces www.halfdog.net
text/xml
URL Logo MISC www.halfdog.net/Security/2015/PtChownArbitraryPtsAccessViaUserNamespace/
USN-2985-1: GNU C Library vulnerabilities | Ubuntu www.ubuntu.com
text/html
URL Logo UBUNTU USN-2985-1
oss-security - Access to /dev/pts devices via pt_chown and user namespaces www.openwall.com
text/html
URL Logo MLIST [oss-security] 20160223 Access to /dev/pts devices via pt_chown and user namespaces

Known Affected Configurations (CPE V2.3)

Type Vendor Product Version Update Edition Language
Operating
System
CanonicalUbuntu Linux12.04AllAllAll
Operating
System
CanonicalUbuntu Linux14.04AllAllAll
Operating
System
CanonicalUbuntu Linux15.10AllAllAll
Operating
System
CanonicalUbuntu Linux12.04AllAllAll
Operating
System
CanonicalUbuntu Linux14.04AllAllAll
Operating
System
CanonicalUbuntu Linux15.10AllAllAll
Operating
System
DebianDebian Linux8.0AllAllAll
Operating
System
DebianDebian Linux8.0AllAllAll
ApplicationGnuGlibcAllAllAllAll
ApplicationGnuGlibcAllAllAllAll
  • cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*:
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*:
  • cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:*:
  • cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*:
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*:
  • cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:*:
  • cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*:
  • cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*:
  • cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*:
  • cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*: