PT-2019-10270 · Systemd+1 · Systemd+1

Setharnold · Published 2019-05-17 · Updated 2025-05-05 · CVE-2018-20839

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions: systemd version 242

Description: The issue allows attackers to read cleartext passwords in certain circumstances, such as watching a shutdown, or using Ctrl-Alt-F1 and Ctrl-Alt-F2. This occurs because the KDGKBMODE (aka current keyboard mode) check is mishandled.

Recommendations: For systemd version 242, consider updating to a newer version that handles the KDGKBMODE check correctly to prevent the exposure of cleartext passwords. As a temporary workaround, restrict access to the system during shutdown or when switching between terminals using Ctrl-Alt-F1 and Ctrl-Alt-F2 to minimize the risk of exploitation.

Fix

Related Identifiers

ALT-PU-2019-2645

ALT-PU-2020-1301

CVE-2018-20839

Affected Products

Alt Linux

Systemd

References · 22

• https://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322f · Patch
• https://github.com/systemd/systemd/pull/12378 · Patch
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-20386 · Security Note
• https://osv.dev/vulnerability/CVE-2018-20839 · Vendor Advisory
• https://errata.altlinux.org/ALT-PU-2020-1301 · Vendor Advisory
• https://errata.altlinux.org/ALT-PU-2019-2645 · Vendor Advisory
• https://bdu.fstec.ru/vul/2020-05729 · Security Note
• https://bdu.fstec.ru/vul/2020-02039 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2018-20839 · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-1712 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2018-20839 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2018-20839 · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-20839 · Security Note
• https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993 · Note
• https://security.netapp.com/advisory/ntap-20190530-0002 · Note