Vulnerability 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 Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Systemd Project | Systemd | <= 241 |
| Redhat | Enterprise Linux | 7.0 |
| Fedoraproject | Fedora | 30 |
| Debian | Debian Linux | 8.0 |
Related Weaknesses (CWE)
References
- http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00062.htmlThird Party Advisory
- http://packetstormsecurity.com/files/152610/systemd-Seat-Verification-Active-SesExploitThird Party AdvisoryVDB Entry
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3842Issue TrackingThird Party Advisory
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e3
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8
- https://lists.debian.org/debian-lts-announce/2019/04/msg00022.htmlThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://www.exploit-db.com/exploits/46743/ExploitThird Party AdvisoryVDB Entry
- http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00062.htmlThird Party Advisory
- http://packetstormsecurity.com/files/152610/systemd-Seat-Verification-Active-SesExploitThird Party AdvisoryVDB Entry
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3842Issue TrackingThird Party Advisory
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e3
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8
- https://lists.debian.org/debian-lts-announce/2019/04/msg00022.htmlThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
FAQ
What is CVE-2019-3842?
CVE-2019-3842 is a vulnerability with a CVSS score of 7.0 (HIGH). 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 configu...
How severe is CVE-2019-3842?
CVE-2019-3842 has been rated HIGH with a CVSS base score of 7.0/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2019-3842?
Check the references section above for vendor advisories and patch information. Affected products include: Systemd Project Systemd, Redhat Enterprise Linux, Fedoraproject Fedora, Debian Debian Linux.