High severity · published Apr 9, 2019
CVE-2019-3842
In systemd before v242-rc4, it was discovered that pam_systemd does not properly sanitize the environment before using the XDG_SEAT variable
7.0
CVSS
1.2%
EPSS
No
On KEV
Description
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".
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 68% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
8.0 · source: NVD
EL
Enterprise Linux · Redhat
7.0 · source: NVD
FE
Fedora · Fedoraproject
30 · source: NVD
SY
Systemd · Systemd Project
through 241; 242; 242; 242 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-3842
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-3842
Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00062.html
Exploit
http://packetstormsecurity.com/files/152610/systemd-Seat-Verification-Active-Session-Spoofing.html
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3842
lists.apache.org
https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2019/04/msg00022.html
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