How severe is CVE-2021-38991?

CVE-2021-38991 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-38991 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-38991?

CVE-2021-38991 primarily affects Ibm Vios. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-38991?

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-2021-38991 published?

CVE-2021-38991 was published on 2022-01-11 and last updated on 2026-06-17.

CVE-2021-38991

CVE-2021-38991 is a high-severity vulnerability in Ibm Vios with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Ibm Vios
Published: 2022-01-11
Last modified: 2026-06-17

Description

IBM AIX 7.0, 7.1, 7.2, and VIOS 3.1 could allow a non-privileged local user to exploit a vulnerability in the lscore command which could lead to code execution. IBM X-Force ID: 212953.

Frequently asked questions

What is CVE-2021-38991?: IBM AIX 7.0, 7.1, 7.2, and VIOS 3.1 could allow a non-privileged local user to exploit a vulnerability in the lscore command which could lead to code execution. IBM X-Force ID: 212953.
How severe is CVE-2021-38991?: CVE-2021-38991 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-38991 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38991?: CVE-2021-38991 primarily affects Ibm Vios. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-38991?: 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-2021-38991 published?: CVE-2021-38991 was published on 2022-01-11 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:ibm:vios:3.1:*:*:*:*:*:*:*
cpe:2.3:o:ibm:aix:7.0:*:*:*:*:*:*:*
cpe:2.3:o:ibm:aix:7.1:*:*:*:*:*:*:*
cpe:2.3:o:ibm:aix:7.2:*:*:*:*:*:*:*

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