Systemd
CVE-2019-3842
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Authorization verification
MITRE ATT&CK
1 technique across 1 tactic: Defense Evasion The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 7.0 (HIGH). Attack characteristics: local attack vector, high complexity, low privileges required, no user interaction not required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | Successful exploitation could compromise the high-severity affected system. |
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Alert meAnalysisAI
In systemd before v242-rc4, it was discovered that pam_systemd does not properly sanitize the environment before using the XDG_SEAT variable. Rated high severity (CVSS 7.0). Public exploit code available and no vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified under CWE-285. In systemd before v242-rc4, it was discovered that pam_systemd does not properly sanitize the environment before using the XDG_SEAT variable. It is possible for an attacker, in some particular configurations, to set a XDG_SEAT environment variable which allows for commands to be checked against polkit policies using the "allow_active" element rather than "allow_any". Affected products include: Systemd Project Systemd, Redhat Enterprise Linux, Fedoraproject Fedora, Debian Debian Linux.
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Severity by source
AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
In systemd before v242-rc4, it was discovered that pam_systemd does not properly sanitize the environment before using the XDG_SEAT variable. It is possible for an attacker, in some particular configurations, to set a XDG_SEAT environment variable which allows for commands to be checked against polkit policies using the "allow_active" element rather than "allow_any".
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)NVD
Stack-based buffer overflow in the getpwnam and getgrnam functions of the NSS module nss-mymachines in systemd. Rated cr
Integer overflow in the valid_user_field function in journal/journald-native.c in systemd allows remote attackers to cau
systemd before 247 does not adequately block local privilege escalation for some Sudo configurations, e.g., plausible su
A flaw in systemd v228 in /src/basic/fs-util.c caused world writable suid files to be created when using the systemd tim
It was discovered that a systemd service that uses DynamicUser property can get new privileges through the execution of
It was discovered that a systemd service that uses DynamicUser property can create a SUID/SGID binary that would be allo
A vulnerability in unit_deserialize of systemd allows an attacker to supply arbitrary state across systemd re-execution
systemd-tmpfiles in systemd through 237 mishandles symlinks present in non-terminal path components, which allows local
basic/unit-name.c in systemd prior to 246.15, 247.8, 248.5, and 249.1 has a Memory Allocation with an Excessive Size Val
A race condition in chown_one() of systemd allows an attacker to cause systemd to set arbitrary permissions on arbitrary
systemd v233 and earlier fails to safely parse usernames starting with a numeric digit (e.g. Rated critical severity (CV
A use-after-free vulnerability was found in systemd. Rated critical severity (CVSS 9.8), this vulnerability is remotely
NVD
CVE.org
EPSS
Exploit-DB
GitHub PoC