CVE-2026-20256
What it is
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 cause data exfiltration through classic dashboards by redirecting a victim to an external site using a protocol-relative URL in a drill-down link.<br><br>The vulnerability exists because the URL classifier in classic dashboards only recognizes `http://` and `https://` schemes when checking for external URLs. Protocol-relative URLs such as `//attacker.com` bypass this check entirely, and Splunk Web does not show the external-navigation warning dialog to the victim.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account, but needs a user to act. High risk of data exposure.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 5.7 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-20 · Improper input validation
- Record status
- Analyzed
Affected
- Splunk < 9.3.13
- Splunk < 9.4.12
- Splunk < 10.0.7
- Splunk < 10.2.4
- Splunk Cloud Platform < 9.3.2411.132
- Splunk Cloud Platform < 10.1.2507.23
- Splunk Cloud Platform < 10.2.2510.15
- Splunk Cloud Platform < 10.3.2512.13
Attack profile CVSS 3.1 · 5.7
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-20256.md and follow it. Check whether this project is affected by CVE-2026-20256. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
