Description
In ksh version 20120801, a flaw was found in the way it 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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| KornShell | ksh | 20120801 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 11 | ksh | 2020.0.0-2.1 | — |
| Debian 9 | ksh | 93u+20120801-3.1+deb9u1 | DLA-2284-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | ksh | No fix yet | — |
| Ubuntu 16.04 LTS | ksh | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | ksh | 93u+20120801-1ubuntu0.14.04.1+esm1 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | ksh | 20120801-253.el8_1 | RHSA-2020:0559 |
| RHEL 7 | ksh | 20120801-140.el7_7 | RHSA-2020:0568 |
| RHEL 6 | ksh | 20120801-38.el6_10 | RHSA-2020:0515 |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8.0 E4S | ksh | 20120801-253.el8_0 | RHSA-2020:0431 |
| RHEL 7.6 EUS | ksh | 20120801-140.el7_6 | RHSA-2020:1333 |
| RHEL 7.5 EUS | ksh | 20120801-138.el7_5 | RHSA-2020:1332 |
| RHEL 7.4 TUS | ksh | 20120801-36.el7_4 | RHSA-2020:2210 |
| RHEL 7.4 E4S | ksh | 20120801-36.el7_4 | RHSA-2020:2210 |
| RHEL 7.4 AUS | ksh | 20120801-36.el7_4 | RHSA-2020:2210 |
| RHEL 7.3 AUS | ksh | 20120801-27.el7_3 | RHSA-2020:5351 |
| RHEL 7.2 AUS | ksh | 20120801-26.el7_2 | RHSA-2020:5352 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP5 | ksh | 93vu-19.3.2 | SUSE-SU-2024:2756-1 |
| SLES 12 | ksh | 93vu-19.3.2 | SUSE-SU-2024:2756-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | ksh | 93vu-10.1 | openSUSE-SU-2024:14252-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | ksh | 20120801-253.0.1.el8_1 | ELSA-2020-0559 |
| Oracle Linux 7 | ksh | 20120801-140.0.1.el7_7 | ELSA-2020-0568 |
Advisories 14
- RHSA-2020:1333 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2020:1332 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2020:0568 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2020:0515 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DLA-2284-1 ksh - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2024:2756-1 Security update for ksh SUSE / openSUSE Security Updates · Feb 4, 2026
- RHSA-2020:5352 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2020:5351 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2020:2210 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2020:0559 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2020:0431 Red Hat Security Advisory: ksh security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- openSUSE-SU-2024:14252-1 ksh-93vu-10.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- ELSA-2020-0568 Important: ksh security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Feb 25, 2020
- ELSA-2020-0559 Important: ksh security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Feb 20, 2020
References
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14868
- https://github.com/att/ast/commit/c7de8b641266bac7c77942239ac659edfee9ecd2
- https://support.apple.com/kb/HT211170
- 20200529 APPLE-SA-2020-05-26-3 macOS Catalina 10.15.5, Security Update 2020-003 Mojave, Security Update 2020-003 High Sierra mailing-list
- [debian-lts-announce] 20200720 [SECURITY] [DLA 2284-1] ksh security update mailing-list