CVE-2019-20044

In Zsh before 5.8, attackers able to execute commands can regain privileges dropped by the --no-PRIVILEGED option. Zsh fails to overwrite the saved uid, so the original privileges can be restored by executing MODULE_PATH=/dir/with/module zmodload with a module that calls setuid().

Published: 2020-02-24 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-20044 is rated Moderate Risk (40.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.06%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2019-20044

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-02-17 0.05% 0.06% +0.01%
2 2023-03-07 1.55% 0.05% -1.50%
3 2022-04-01 — 1.55% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-20044

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
7.2 2.0 HIGH
AV:L/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 3.9 10.0 [email protected]

Weakness enumeration for CVE-2019-20044

OS Trackers for CVE-2019-20044

vendor priority summary link
alpine high CVE-2019-20044: 1 source package rows (zsh); 8 state rows across 8 repos (3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 8, open 0. https://security.alpinelinux.org/vuln/CVE-2019-20044
debian not yet assigned CVE-2019-20044 not yet assigned priority: Debian including 1 source packages (zsh), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2019-20044
gentoo normal CVE-2019-20044: 1 GLSA(s) (202003-55), 1 atom(s) (app-shells/zsh); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2019-20044
redhat high — https://access.redhat.com/security/cve/CVE-2019-20044
suse high CVE-2019-20044 severity important: SUSE including 244 source package names (amazon/suse-sles-15-sp1-chost-byos-v20210304-hvm-ssd-x86_64, amazon/suse-sles-15-sp1-chost-byos-v20220127-hvm-ssd-x86_64, …), 429 product×package rows across 194 product lines (HPE Helion OpenStack 8, Image SLES12-SP5-Azure-BYOS, … (194 product lines)): Known Affected 231, Fixed 198. https://www.suse.com/security/cve/CVE-2019-20044/
ubuntu low CVE-2019-20044 low priority: Ubuntu including 1 source packages (zsh), 17 status rows across 17 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 11, released 3, DNE 1, ignored 1, needs-triage 1. https://ubuntu.com/security/CVE-2019-20044

Affected software / configurations for CVE-2019-20044

Vendor Product Version Raw CPE
zsh zsh < 5.8 cpe:2.3:a:zsh:zsh:*:*:*:*:*:*:*:*
fedoraproject fedora 30 cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
fedoraproject fedora 31 cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
apple ipados < 13.5 cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple iphone_os < 13.5 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple mac_os_x < 10.15.5 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple mac_os_x >= 10.13.0, < 10.13.6 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple mac_os_x >= 10.14.0, < 10.14.6 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple mac_os_x >= 10.15, < 10.15.5 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:-:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2018-002:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2018-003:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-001:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-002:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-003:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-004:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-005:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-006:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-007:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2020-001:*:*:*:*:*:*
apple mac_os_x 10.13.6 cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2020-002:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:-:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-001:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-002:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-004:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-005:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-006:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-007:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-001:*:*:*:*:*:*
apple mac_os_x 10.14.6 cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-002:*:*:*:*:*:*
apple tvos < 13.4.5 cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
apple watchos < 6.2.5 cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

References for CVE-2019-20044

URL Tags
http://seclists.org/fulldisclosure/2020/May/49 Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2020/May/53 Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2020/May/55 Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2020/May/59 Mailing List Third Party Advisory
http://zsh.sourceforge.net/releases.html Release Notes Third Party Advisory
https://github.com/XMB5/zsh-privileged-upgrade Broken Link
https://lists.debian.org/debian-lts-announce/2020/03/msg00004.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/12/msg00000.html Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FP64FFIZI2CKQOEAOI5A72PVQULE7ZZC/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PN5V7MPHRRP7QNHOEK56S7QGRU53WUN6/
https://security.gentoo.org/glsa/202003-55 Third Party Advisory
https://support.apple.com/HT211168 Third Party Advisory
https://support.apple.com/HT211170 Third Party Advisory
https://support.apple.com/HT211171 Third Party Advisory
https://support.apple.com/HT211175 Third Party Advisory
https://support.apple.com/kb/HT211168 Third Party Advisory
https://support.apple.com/kb/HT211170 Third Party Advisory
https://support.apple.com/kb/HT211171 Third Party Advisory
https://support.apple.com/kb/HT211175 Third Party Advisory
https://www.zsh.org/mla/zsh-announce/141 Release Notes Vendor Advisory
cvelogic Threat Intelligence