CVE-2018-20839
No known exploitation. EPSS puts it in the 84th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
2.5% chance of exploitation activity in the next 30 days, which ranks it in the 84th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 2596 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Scored 4.3 by NVD.
How it is reached
- Attack Vector PhysicalRequires physical access to the device
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction RequiredA user must click a link, open a file, or perform some action
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
Sources
References in the record
- bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993
- github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322f
- github.com/systemd/systemd/pull/12378
And 3 more references. See all after sign-in
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