CVE-2021-3621
CVE-2021-3621 is a high-severity vulnerability in Redhat Virtualization with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v2: 9.3
- EPSS exploit prediction: 3% (83rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-78
- Affected product: Redhat Virtualization
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is 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.
- How severe is CVE-2021-3621?
- CVE-2021-3621 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-3621 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-3621?
- CVE-2021-3621 primarily affects Redhat Virtualization. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-3621?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-3621 published?
- CVE-2021-3621 was published on 2021-12-23 and last updated on 2026-06-17.
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1975142
- https://lists.debian.org/debian-lts-announce/2023/05/msg00028.html
- https://sssd.io/release-notes/sssd-2.6.0.html
- https://lists.debian.org/debian-lts-announce/2025/02/msg00008.html
Affected products (13)
- cpe:2.3:a:fedoraproject:sssd:2.6.0:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:virtualization:4.0:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:virtualization_host:4.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
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