SARA / Free Tools / CVE / CVE-2019-3842

CVE-2019-3842 — In systemd before v242-rc4, it was discovered that pam_systemd does not properly

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

CVSS
4.5 MEDIUM
EPSS
0.10% (top 73.20%)
CWE
CWE-285
Published
2019-04-09T20:25:01.000Z
Last modified
2025-06-09T15:47:28.243Z
CVSS vector
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L

01What is this vulnerability?

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".

02Affected products

VendorProductVersions
The systemd Projectsystemdv242-rc4

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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