CVE-2015-8777

Publication date 20 January 2016

Last updated 24 July 2024


Ubuntu priority

Cvss 3 Severity Score

5.5 · Medium

Score breakdown

The process_envvars function in elf/rtld.c in the GNU C Library (aka glibc or libc6) before 2.23 allows local users to bypass a pointer-guarding protection mechanism via a zero value of the LD_POINTER_GUARD environment variable.

From the Ubuntu Security Team

Hector Marco and Ismael Ripoll discovered that the GNU C Library allowed the pointer-guarding protection mechanism to be disabled by honoring the LD_POINTER_GUARD environment variable across privilege boundaries. An local attacker could use this to exploit an existing vulnerability more easily.

Status

Package Ubuntu Release Status
eglibc 17.04 zesty Not in release
16.10 yakkety Not in release
16.04 LTS xenial Not in release
15.10 wily Not in release
15.04 vivid Not in release
14.04 LTS trusty
Fixed 2.19-0ubuntu6.8
12.04 LTS precise
Fixed 2.15-0ubuntu10.14
glibc 17.04 zesty
Not affected
16.10 yakkety
Not affected
16.04 LTS xenial
Not affected
15.10 wily
Fixed 2.21-0ubuntu4.2
15.04 vivid Ignored end of life
14.04 LTS trusty Not in release
12.04 LTS precise Not in release

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
glibc

Severity score breakdown

Parameter Value
Base score 5.5 · Medium
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact High
Availability impact None
Vector CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N