How severe is CVE-2021-37939?

CVE-2021-37939 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-2021-37939 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-37939?

CVE-2021-37939 affects Elastic Kibana. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-37939?

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

When was CVE-2021-37939 published?

CVE-2021-37939 was published on 2021-11-18 and last updated on 2026-06-17.

CVE-2021-37939

CVE-2021-37939 is a low-severity vulnerability in Elastic Kibana 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-319.

Key facts

Severity: Low (CVSS 3.x base score 2.7)
CVSS v2: 4.0
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-319
Affected product: Elastic Kibana
Published: 2021-11-18
Last modified: 2026-06-17

Description

It was discovered that Kibana’s JIRA connector & IBM Resilient connector could be used to return HTTP response data on internal hosts, which may be intentionally hidden from public view. Using this vulnerability, a malicious user with the ability to create connectors, could utilize these connectors to view limited HTTP response data on hosts accessible to the cluster.

Frequently asked questions

What is CVE-2021-37939?: It was discovered that Kibana’s JIRA connector & IBM Resilient connector could be used to return HTTP response data on internal hosts, which may be intentionally hidden from public view. Using this vulnerability, a malicious user with the ability to create connectors, could utilize these connectors to view limited HTTP response data on hosts accessible to the cluster.
How severe is CVE-2021-37939?: CVE-2021-37939 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-2021-37939 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-37939?: CVE-2021-37939 affects Elastic Kibana. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-37939?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-37939 published?: CVE-2021-37939 was published on 2021-11-18 and last updated on 2026-06-17.

References

https://discuss.elastic.co/t/kibana-7-15-2-security-update/288923

Affected products (1)

cpe:2.3:a:elastic:kibana:*:*:*:*:*:*:*:*

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