CVE-2018-16838

A flaw was found in sssd Group Policy Objects implementation. When the GPO is not readable by SSSD due to a too strict permission settings on the server side, SSSD will allow all authenticated users to login instead of denying access.

Published: 2019-03-25 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-16838 is rated Moderate Risk (49/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.07%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-16838

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-30 0.92% 1.07% +0.15%
2 2026-03-12 0.97% 0.92% -0.05%
3 2026-02-23 — 0.97% —

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-16838

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.4 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.5 [email protected]
5.4 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.5 [email protected]
5.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.0 4.9 [email protected]

Weakness enumeration for CVE-2018-16838

OS Trackers for CVE-2018-16838

vendor priority summary link
debian not yet assigned CVE-2018-16838 not yet assigned priority: Debian including 1 source packages (sssd), 4 status rows across 4 suites (bookworm, bullseye, sid, trixie): resolved 4. https://security-tracker.debian.org/tracker/CVE-2018-16838
redhat low — https://access.redhat.com/security/cve/CVE-2018-16838
suse medium CVE-2018-16838 severity moderate: SUSE including 435 source package names (libipa_hbac-1.16.4-21.el7, libipa_hbac-2.2.0-19.el8, …), 570 product×package rows across 40 product lines (SLES for SAP Applications 11 SP3, SUSE Liberty Linux 7, … (40 product lines)): Fixed 545, Known Not Affected 25. https://www.suse.com/security/cve/CVE-2018-16838/
ubuntu low CVE-2018-16838 low priority: Ubuntu including 1 source packages (sssd), 19 status rows across 19 suites (bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 13, ignored 2, released 2, DNE 1, needed 1. https://ubuntu.com/security/CVE-2018-16838

Affected software / configurations for CVE-2018-16838

Vendor Product Version Raw CPE
fedoraproject sssd — cpe:2.3:a:fedoraproject:sssd:-:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*

References for CVE-2018-16838

cvelogic Threat Intelligence