How severe is CVE-2021-23338?

CVE-2021-23338 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-23338 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23338?

CVE-2021-23338 affects Microsoft Qlib. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23338?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-23338 published?

CVE-2021-23338 was published on 2021-02-15 and last updated on 2026-06-17.

CVE-2021-23338

CVE-2021-23338 is a medium-severity vulnerability in Microsoft Qlib with a CVSS 3.x base score of 6.6. 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-502.

Key facts

Severity: Medium (CVSS 3.x base score 6.6)
CVSS v2: 6.5
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Microsoft Qlib
Published: 2021-02-15
Last modified: 2026-06-17

Description

This affects all versions of package qlib. The workflow function in cli part of qlib was using an unsafe YAML load function.

Frequently asked questions

What is CVE-2021-23338?: This affects all versions of package qlib. The workflow function in cli part of qlib was using an unsafe YAML load function.
How severe is CVE-2021-23338?: CVE-2021-23338 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-23338 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23338?: CVE-2021-23338 affects Microsoft Qlib. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23338?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-23338 published?: CVE-2021-23338 was published on 2021-02-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microsoft:qlib:*:*:*:*:*:*:*:*

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