CVE-2021-3621

A flaw was found in SSSD, where the sssctl command was vulnerable to shell command injection via the logs-fetch and cache-expire subcommands. This flaw allows an attacker to trick the root user into running a specially crafted sssctl command, such as via sudo, to gain root access. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Published: 2021-12-23 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-3621 is rated High Risk (66.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.52%). EPSS rose +2.14% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize 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-2021-3621

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 2026-06-15 0.38% 2.52% +2.14%
2 2026-03-21 0.63% 0.38% -0.24%
3 2026-03-20 — 0.63% —

Full EPSS history (19 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3621

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H 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:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
9.3 2.0 HIGH
AV:N/AC:M/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 8.6 10.0 [email protected]

Weakness enumeration for CVE-2021-3621

OS Trackers for CVE-2021-3621

vendor priority summary link
debian not yet assigned CVE-2021-3621 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-2021-3621
gentoo normal CVE-2021-3621: 1 GLSA(s) (202407-05), 1 atom(s) (sys-auth/sssd); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-3621
redhat high — https://access.redhat.com/security/cve/CVE-2021-3621
suse medium CVE-2021-3621 severity moderate: SUSE including 399 source package names (libipa_hbac-1.16.5-10.el7_9.10, libipa_hbac-2.4.0-9.el8_4.2, …), 984 product×package rows across 60 product lines (HPE Helion OpenStack 8, SUSE CaaS Platform 4.0, … (60 product lines)): Fixed 859, Known Not Affected 125. https://www.suse.com/security/cve/CVE-2021-3621/
ubuntu medium CVE-2021-3621 medium priority: Ubuntu including 1 source packages (sssd), 8 status rows across 8 suites (bionic, focal, hirsute, impish, jammy, trusty, upstream, xenial): released 5, DNE 1, needs-triage 1, not-affected 1. https://ubuntu.com/security/CVE-2021-3621

Affected software / configurations for CVE-2021-3621

Vendor Product Version Raw CPE
fedoraproject sssd 2.6.0 cpe:2.3:a:fedoraproject:sssd:2.6.0:*:*:*:*:*:*:*
redhat virtualization 4.0 cpe:2.3:a:redhat:virtualization:4.0:*:*:*:*:*:*:*
redhat virtualization_host 4.0 cpe:2.3:a:redhat:virtualization_host:4.0:*:*:*:*:*:*:*
redhat enterprise_linux 6.0 cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux_eus 8.1 cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:*
redhat enterprise_linux_eus 8.2 cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.2 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.4 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.2 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.4 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

References for CVE-2021-3621

cvelogic Threat Intelligence