CVE-2020-14367

A flaw was found in chrony versions before 3.5.1 when creating the PID file under the /var/run/chrony folder. The file is created during chronyd startup while still running as the root user, and when it's opened for writing, chronyd does not check for an existing symbolic link with the same file name. This flaw allows an attacker with privileged access to create a symlink with the default PID file name pointing to any destination file in the system, resulting in data loss and a denial of service due to the path traversal.

CVSS v3 6.0 MEDIUM
CVSS v2.0 3.6 LOW

6.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

3.6^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:L/Au:N/C:N/I:P/A:P

Exploitability : 3.9 / Impact : 4.9

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://bugzilla.redhat.com/show_bug.cgi?id=1870298	Issue Tracking Patch Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6WKABKNLCSC3MACCWU6OM2YGWVWFWFMU/
https://security.gentoo.org/glsa/202008-23	Third Party Advisory
https://usn.ubuntu.com/4475-1/	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:tuxfamily:chrony:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*

Configuration 3 (hide)

OR	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::
	cpe:2.3:o:canonical:ubuntu_linux:20.04::::lts:::

History

No history.

Information

Published : 2020-08-24 15:15

Updated : 2023-11-07 03:17

NVD link : CVE-2020-14367

Mitre link : CVE-2020-14367

CVE.ORG link : CVE-2020-14367

JSON object : View

Products Affected

canonical

ubuntu_linux

fedoraproject

fedora

tuxfamily

chrony

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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