How severe is CVE-2021-25737?

CVE-2021-25737 has a CVSS 3.x base score of 2.7, rated low severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-25737 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25737?

CVE-2021-25737 primarily affects Kubernetes. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-25737?

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

When was CVE-2021-25737 published?

CVE-2021-25737 was published on 2021-09-06 and last updated on 2026-06-17.

CVE-2021-25737

CVE-2021-25737 is a low-severity vulnerability in Kubernetes with a CVSS 3.x base score of 2.7. 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-601.

Key facts

Severity: Low (CVSS 3.x base score 2.7)
CVSS v2: 4.9
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-601
Affected product: Kubernetes
Published: 2021-09-06
Last modified: 2026-06-17

Description

A security issue was discovered in Kubernetes where a user may be able to redirect pod traffic to private networks on a Node. Kubernetes already prevents creation of Endpoint IPs in the localhost or link-local range, but the same validation was not performed on EndpointSlice IPs.

Frequently asked questions

What is CVE-2021-25737?: A security issue was discovered in Kubernetes where a user may be able to redirect pod traffic to private networks on a Node. Kubernetes already prevents creation of Endpoint IPs in the localhost or link-local range, but the same validation was not performed on EndpointSlice IPs.
How severe is CVE-2021-25737?: CVE-2021-25737 has a CVSS 3.x base score of 2.7, rated low severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-25737 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25737?: CVE-2021-25737 primarily affects Kubernetes. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-25737?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-25737 published?: CVE-2021-25737 was published on 2021-09-06 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:kubernetes:kubernetes:*:*:*:*:*:*:*:*
cpe:2.3:a:kubernetes:kubernetes:1.21.0:-:*:*:*:*:*:*

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