Fedora 27 : glibc (2018-7714b514e2)

High Nessus Plugin ID 106279

Synopsis

The remote Fedora host is missing a security update.

Description

This update addresses two security vulnerabilities :

- CVE-2017-16997: Check for empty tokens before dynamic string token expansion in the dynamic linker, so that pre-existing privileged programs with `$ORIGIN` rpaths/runpaths do not cause the dynamic linker to search the current directory, potentially leading to privilege escalation. (RHBZ#1526866).

- CVE-2018-1000001: `getcwd` would sometimes return a non-absolute path, confusing the `realpath` function, leading to privilege escalation in conjunction with user namespaces. (RHBZ#1533837)

In addition, this update changes the thread stack size accounting to provide additional stack space compared to previous glibc versions.
For some applications (`nptd` in particular), the `PTHREAD_STACK_MIN` stack size was too small on x86-64 machines with AVX-512 support (RHBZ#1527887).

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Update the affected glibc package.

See Also

https://bodhi.fedoraproject.org/updates/FEDORA-2018-7714b514e2

Plugin Details

Severity: High

ID: 106279

File Name: fedora_2018-7714b514e2.nasl

Version: 3.4

Type: local

Agent: unix

Published: 2018/01/24

Updated: 2019/04/05

Dependencies: 12634

Risk Information

Risk Factor: High

CVSS v2.0

Base Score: 9.3

Temporal Score: 7.7

Vector: CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C

Temporal Vector: CVSS2#E:F/RL:OF/RC:C

CVSS v3.0

Base Score: 7.8

Temporal Score: 7.2

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

Temporal Vector: CVSS:3.0/E:F/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:fedoraproject:fedora:glibc, cpe:/o:fedoraproject:fedora:27

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2018/01/23

Exploitable With

Metasploit (glibc "realpath()" Privilege Escalation)

Reference Information

CVE: CVE-2017-16997, CVE-2018-1000001