CVE-2018-20839
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.
Does this matter?
Lower severity and a low EPSS score (2.48%). Track it; it rarely justifies an emergency change on its own.
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 3.1
- 4.3 MEDIUMCVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- EPSS
- 2.48% probability · 84th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- systemd project/systemd · netapp/cn1610 firmware · netapp/snapprotect · netapp/solidfire \& hci management node
- Source
- cve@mitre.org
EPSS 2.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.securityfocus.com/bid/108389Broken Link, Third Party Advisory, VDB Entry
- https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993Issue Tracking, Third Party Advisory
- https://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322fPatch
- https://github.com/systemd/systemd/pull/12378Issue Tracking, Patch
- https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3EMailing List
- https://security.netapp.com/advisory/ntap-20190530-0002/Third Party Advisory
- http://www.securityfocus.com/bid/108389Broken Link, Third Party Advisory, VDB Entry
- https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993Issue Tracking, Third Party Advisory
- https://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322fPatch
- https://github.com/systemd/systemd/pull/12378Issue Tracking, Patch
- https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3EMailing List
- https://security.netapp.com/advisory/ntap-20190530-0002/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.