How severe is CVE-2026-20255?

CVE-2026-20255 has a CVSS 3.x base score of 5.7, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-20255 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-20255?

CVE-2026-20255 primarily affects Splunk. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-20255?

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

Does CVE-2026-20255 have an EU (EUVD) identifier?

Yes. CVE-2026-20255 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-36083.

When was CVE-2026-20255 published?

CVE-2026-20255 was published on 2026-06-10 and last updated on 2026-06-17.

CVE-2026-20255

CVE-2026-20255 is a medium-severity vulnerability in Splunk with a CVSS 3.x base score of 5.7. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.7)
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-36083
Weakness: CWE-20
Affected product: Splunk
Published: 2026-06-10
Last modified: 2026-06-17

Description

In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.13, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user that does not hold the "admin" or "power" Splunk roles could craft a malicious classic dashboard that exfiltrates sensitive data to an external server. The vulnerability exists because URL validation on the external content dialog is incomplete, which can allow for requests to untrusted domains when a user interacts with a crafted dashboard.

Frequently asked questions

What is CVE-2026-20255?: In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, and Splunk Cloud Platform versions below 10.3.2512.13, 10.2.2510.15, 10.1.2507.23, and 9.3.2411.132, a low-privileged user that does not hold the "admin" or "power" Splunk roles could craft a malicious classic dashboard that exfiltrates sensitive data to an external server. The vulnerability exists because URL validation on the external content dialog is incomplete, which can allow for requests to untrusted domains when a user interacts with a crafted dashboard.
How severe is CVE-2026-20255?: CVE-2026-20255 has a CVSS 3.x base score of 5.7, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-20255 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-20255?: CVE-2026-20255 primarily affects Splunk. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-20255?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-20255 have an EU (EUVD) identifier?: Yes. CVE-2026-20255 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-36083.
When was CVE-2026-20255 published?: CVE-2026-20255 was published on 2026-06-10 and last updated on 2026-06-17.

References

https://advisory.splunk.com/advisories/SVD-2026-0605

Affected products (2)

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

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