9.8
CRITICAL
CVE-2018-20839
OpenSSH systemd VT1 Cleartext Password Disclosure
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.

INFO

Published Date :

May 17, 2019, 4:29 a.m.

Last Modified :

Nov. 7, 2023, 2:56 a.m.

Source :

[email protected]

Remotely Exploitable :

Yes !

Impact Score :

5.9

Exploitability Score :

3.9
Public PoC/Exploit Available at Github

CVE-2018-20839 has a 4 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

Affected Products

The following products are affected by CVE-2018-20839 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Netapp solidfire_\&_hci_management_node
2 Netapp cn1610_firmware
3 Netapp snapprotect
1 Systemd_project systemd
: Total Affected Vendor : 2 | Products : 4
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2018-20839.

URL Resource
http://www.securityfocus.com/bid/108389 Third Party Advisory VDB Entry
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993 Issue Tracking Third Party Advisory
https://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322f Patch Third Party Advisory
https://github.com/systemd/systemd/pull/12378 Third Party Advisory
https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E
https://security.netapp.com/advisory/ntap-20190530-0002/ Patch Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Profile Photo
juaromu/wazuh-snyk

None

Shell

Updated: 1 year, 5 months ago
2 stars 2 fork 2 watcher
Born at : Nov. 11, 2021, 4:10 a.m. This repo has been linked 1 different CVEs too.
Profile Photo
garethr/snykout

A command line tool which provides an alternative interface to snyk test

snyk

Makefile Dockerfile Crystal Open Policy Agent

Updated: 2 years, 7 months ago
4 stars 3 fork 3 watcher
Born at : Aug. 31, 2020, 8:31 a.m. This repo has been linked 82 different CVEs too.
Profile Photo
revl-ca/scan-docker-image

None

Shell

Updated: 5 years, 2 months ago
0 stars 0 fork 0 watcher
Born at : July 18, 2019, 10:49 p.m. This repo has been linked 124 different CVEs too.
Profile Photo
simonsdave/clair-cicd

Making CoreOS' Clair easily work in CI/CD pipelines

security-tools security-audit dev-ops ci-cd clair static-analysis docker vulnerabilities

Shell Python Dockerfile Ruby

Updated: 7 months, 3 weeks ago
29 stars 8 fork 8 watcher
Born at : May 13, 2016, 7:04 p.m. This repo has been linked 7 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2018-20839 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2018-20839 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Added Reference MITRE https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E [No types assigned]
    Removed Reference MITRE https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772@%3Cdev.mina.apache.org%3E
  • Modified Analysis by [email protected]

    Feb. 20, 2022

    Action Type Old Value New Value
    Removed CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:N/A:N)
    Added CVSS V2 NIST (AV:N/AC:M/Au:N/C:P/I:N/A:N)
    Removed CVSS V3 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type http://www.securityfocus.com/bid/108389 No Types Assigned http://www.securityfocus.com/bid/108389 Third Party Advisory, VDB Entry
    Changed Reference Type https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772@%3Cdev.mina.apache.org%3E No Types Assigned https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772@%3Cdev.mina.apache.org%3E Mailing List, Third Party Advisory
    Changed Reference Type https://security.netapp.com/advisory/ntap-20190530-0002/ No Types Assigned https://security.netapp.com/advisory/ntap-20190530-0002/ Patch, Third Party Advisory
    Added CPE Configuration AND OR *cpe:2.3:o:netapp:cn1610_firmware:-:*:*:*:*:*:*:* OR cpe:2.3:h:netapp:cn1610:-:*:*:*:*:*:*:*
    Added CPE Configuration OR *cpe:2.3:a:netapp:snapprotect:-:*:*:*:*:*:*:* *cpe:2.3:a:netapp:solidfire_\&_hci_management_node:-:*:*:*:*:*:*:*
  • CPE Deprecation Remap by [email protected]

    Jan. 28, 2022

    Action Type Old Value New Value
    Changed CPE Configuration OR *cpe:2.3:a:freedesktop:systemd:242:-:*:*:*:*:*:* OR *cpe:2.3:a:systemd_project:systemd:242:-:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Feb. 25, 2021

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772@%3Cdev.mina.apache.org%3E [No Types Assigned]
  • CWE Remap by [email protected]

    Aug. 24, 2020

    Action Type Old Value New Value
    Changed CWE CWE-255 CWE-200
  • CVE Modified by [email protected]

    May. 30, 2019

    Action Type Old Value New Value
    Added Reference https://security.netapp.com/advisory/ntap-20190530-0002/ [No Types Assigned]
  • CVE Modified by [email protected]

    May. 21, 2019

    Action Type Old Value New Value
    Added Reference http://www.securityfocus.com/bid/108389 [No Types Assigned]
  • Initial Analysis by [email protected]

    May. 20, 2019

    Action Type Old Value New Value
    Added CVSS V2 (AV:N/AC:L/Au:N/C:P/I:N/A:N)
    Added CVSS V3 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322f No Types Assigned https://github.com/systemd/systemd/commit/9725f1a10f80f5e0ae7d9b60547458622aeb322f Patch, Third Party Advisory
    Changed Reference Type https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993 No Types Assigned https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1803993 Issue Tracking, Third Party Advisory
    Changed Reference Type https://github.com/systemd/systemd/pull/12378 No Types Assigned https://github.com/systemd/systemd/pull/12378 Third Party Advisory
    Added CWE CWE-255
    Added CPE Configuration OR *cpe:2.3:a:freedesktop:systemd:242:-:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2018-20839 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2018-20839 weaknesses.

CAPEC-13: Subverting Environment Variable Values Subverting Environment Variable Values CAPEC-22: Exploiting Trust in Client Exploiting Trust in Client CAPEC-59: Session Credential Falsification through Prediction Session Credential Falsification through Prediction CAPEC-60: Reusing Session IDs (aka Session Replay) Reusing Session IDs (aka Session Replay) CAPEC-79: Using Slashes in Alternate Encoding Using Slashes in Alternate Encoding CAPEC-116: Excavation Excavation CAPEC-169: Footprinting Footprinting CAPEC-224: Fingerprinting Fingerprinting CAPEC-285: ICMP Echo Request Ping ICMP Echo Request Ping CAPEC-287: TCP SYN Scan TCP SYN Scan CAPEC-290: Enumerate Mail Exchange (MX) Records Enumerate Mail Exchange (MX) Records CAPEC-291: DNS Zone Transfers DNS Zone Transfers CAPEC-292: Host Discovery Host Discovery CAPEC-293: Traceroute Route Enumeration Traceroute Route Enumeration CAPEC-294: ICMP Address Mask Request ICMP Address Mask Request CAPEC-295: Timestamp Request Timestamp Request CAPEC-296: ICMP Information Request ICMP Information Request CAPEC-297: TCP ACK Ping TCP ACK Ping CAPEC-298: UDP Ping UDP Ping CAPEC-299: TCP SYN Ping TCP SYN Ping CAPEC-300: Port Scanning Port Scanning CAPEC-301: TCP Connect Scan TCP Connect Scan CAPEC-302: TCP FIN Scan TCP FIN Scan CAPEC-303: TCP Xmas Scan TCP Xmas Scan CAPEC-304: TCP Null Scan TCP Null Scan CAPEC-305: TCP ACK Scan TCP ACK Scan CAPEC-306: TCP Window Scan TCP Window Scan CAPEC-307: TCP RPC Scan TCP RPC Scan CAPEC-308: UDP Scan UDP Scan CAPEC-309: Network Topology Mapping Network Topology Mapping CAPEC-310: Scanning for Vulnerable Software Scanning for Vulnerable Software CAPEC-312: Active OS Fingerprinting Active OS Fingerprinting CAPEC-313: Passive OS Fingerprinting Passive OS Fingerprinting CAPEC-317: IP ID Sequencing Probe IP ID Sequencing Probe CAPEC-318: IP 'ID' Echoed Byte-Order Probe IP 'ID' Echoed Byte-Order Probe CAPEC-319: IP (DF) 'Don't Fragment Bit' Echoing Probe IP (DF) 'Don't Fragment Bit' Echoing Probe CAPEC-320: TCP Timestamp Probe TCP Timestamp Probe CAPEC-321: TCP Sequence Number Probe TCP Sequence Number Probe CAPEC-322: TCP (ISN) Greatest Common Divisor Probe TCP (ISN) Greatest Common Divisor Probe CAPEC-323: TCP (ISN) Counter Rate Probe TCP (ISN) Counter Rate Probe CAPEC-324: TCP (ISN) Sequence Predictability Probe TCP (ISN) Sequence Predictability Probe CAPEC-325: TCP Congestion Control Flag (ECN) Probe TCP Congestion Control Flag (ECN) Probe CAPEC-326: TCP Initial Window Size Probe TCP Initial Window Size Probe CAPEC-327: TCP Options Probe TCP Options Probe CAPEC-328: TCP 'RST' Flag Checksum Probe TCP 'RST' Flag Checksum Probe CAPEC-329: ICMP Error Message Quoting Probe ICMP Error Message Quoting Probe CAPEC-330: ICMP Error Message Echoing Integrity Probe ICMP Error Message Echoing Integrity Probe CAPEC-472: Browser Fingerprinting Browser Fingerprinting CAPEC-497: File Discovery File Discovery CAPEC-508: Shoulder Surfing Shoulder Surfing CAPEC-573: Process Footprinting Process Footprinting CAPEC-574: Services Footprinting Services Footprinting CAPEC-575: Account Footprinting Account Footprinting CAPEC-576: Group Permission Footprinting Group Permission Footprinting CAPEC-577: Owner Footprinting Owner Footprinting CAPEC-616: Establish Rogue Location Establish Rogue Location CAPEC-643: Identify Shared Files/Directories on System Identify Shared Files/Directories on System CAPEC-646: Peripheral Footprinting Peripheral Footprinting CAPEC-651: Eavesdropping Eavesdropping
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

1.75 }} 0.00%

score

0.87994

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
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