How severe is CVE-2021-26253?

CVE-2021-26253 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-26253 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26253?

CVE-2021-26253 affects Splunk. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26253?

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-2021-26253 published?

CVE-2021-26253 was published on 2022-05-06 and last updated on 2026-06-17.

CVE-2021-26253

CVE-2021-26253 is a high-severity vulnerability in Splunk with a CVSS 3.x base score of 8.1. 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-287.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Splunk
Published: 2022-05-06
Last modified: 2026-06-17

Description

A potential vulnerability in Splunk Enterprise's implementation of DUO MFA allows for bypassing the MFA verification in Splunk Enterprise versions before 8.1.6. The potential vulnerability impacts Splunk Enterprise instances configured to use DUO MFA and does not impact or affect a DUO product or service.

Frequently asked questions

What is CVE-2021-26253?: A potential vulnerability in Splunk Enterprise's implementation of DUO MFA allows for bypassing the MFA verification in Splunk Enterprise versions before 8.1.6. The potential vulnerability impacts Splunk Enterprise instances configured to use DUO MFA and does not impact or affect a DUO product or service.
How severe is CVE-2021-26253?: CVE-2021-26253 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-26253 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26253?: CVE-2021-26253 affects Splunk. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26253?: 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-2021-26253 published?: CVE-2021-26253 was published on 2022-05-06 and last updated on 2026-06-17.

References

https://www.splunk.com/en_us/product-security/announcements/svd-2022-0504.html

Affected products (1)

cpe:2.3:a:splunk:splunk:*:*:*:*:enterprise:*:*:*

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