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CVE-2018-20839

Published: May 17, 2019Updated: May 5, 2025 Sources: CVE List NVDNVD-CWE-noinfo
NVD MITRE
4.3CVSSMEDIUM
EPSS Score
2.5%
Top 17.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

systemd 242 changes the VT1 mode upon a logout, which 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.

CVSS Vector Breakdown

AV:PAC:LPR:NUI:RS:UC:HI:NA:N
Exploitability
AV:PAttack Vector
Physical
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None
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Weaknesses

NVD-CWE-noinfo

Affected Products

n/an/a
systemdsystemd project
On-prem
Operating Systems / linux-distro
cn1610 firmwarenetappHardware Firmware
snapprotectnetappHardware Firmware
solidfire \& hci management nodenetappHardware Firmware
systemd projectoss-projectOperating Systemsaka systemd
netappcommercialUSHardware Firmware

Exploitability

Official Patch Available

References

https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993
bugs.launchpad.net
https://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322f
github.com
https://github.com/systemd/systemd/pull/12378
github.com
and 3 more references View all →

Timeline

Published
May 17, 2019
Last Updated
May 5, 2025

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