How severe is CVE-2021-3998?

CVE-2021-3998 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-3998 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3998?

CVE-2021-3998 primarily affects Gnu Glibc. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3998?

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-2021-3998 published?

CVE-2021-3998 was published on 2022-08-24 and last updated on 2026-06-17.

CVE-2021-3998

CVE-2021-3998 is a high-severity vulnerability in Gnu Glibc with a CVSS 3.x base score of 7.5. 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-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Gnu Glibc
Published: 2022-08-24
Last modified: 2026-06-17

Description

A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.

Frequently asked questions

What is CVE-2021-3998?: A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
How severe is CVE-2021-3998?: CVE-2021-3998 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-3998 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3998?: CVE-2021-3998 primarily affects Gnu Glibc. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3998?: 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-2021-3998 published?: CVE-2021-3998 was published on 2022-08-24 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*

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