A flaw was found in the way ksh evaluates certain environment variables. An attacker could use this flaw to override or bypass environment restrictions to execute shell commands. Services and applications that allow remote unauthenticated attackers to provide one of those environment variables could allow them to exploit this issue remotely.
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14868
https://github.com/att/ast/commit/c7de8b641266bac7c77942239ac659edfee9ecd2
https://support.apple.com/kb/HT211170
http://seclists.org/fulldisclosure/2020/May/53
https://lists.debian.org/debian-lts-announce/2020/07/msg00015.html
https://access.redhat.com/errata/RHSA-2020:2210
https://access.redhat.com/errata/RHSA-2020:1332
https://access.redhat.com/errata/RHSA-2020:5351
https://access.redhat.com/errata/RHSA-2020:5352
https://bugzilla.redhat.com/show_bug.cgi?id=1757324
https://access.redhat.com/errata/RHSA-2020:0568
https://access.redhat.com/errata/RHSA-2020:0515
https://access.redhat.com/errata/RHSA-2020:0559
https://access.redhat.com/errata/RHSA-2020:0431
Source: MITRE
Published: 2020-04-02
Updated: 2023-02-02
Type: CWE-77
Base Score: 7.2
Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C
Impact Score: 10
Exploitability Score: 3.9
Severity: HIGH
Base Score: 7.8
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 1.8
Severity: HIGH