What products are affected by CVE-2026-20253?

CVE-2026-20253 affects Splunk Enterprise. Refer to the vendor advisory and NVD record for affected versions.

Is there a public exploit for CVE-2026-20253?

Yes. Public exploit code or proof-of-concept has been identified for CVE-2026-20253. This lowers the barrier for exploitation and increases the urgency of patching. Organizations should prioritize remediation immediately.

What is the EPSS score for CVE-2026-20253?

CVE-2026-20253 has an EPSS score of 10.0%, placing it in the 95th percentile. This means it has a 10.0% probability of being exploited in the next 30 days, higher than 95% of all known vulnerabilities. EPSS (Exploit Prediction Scoring System) is maintained by FIRST and uses real-world threat data to estimate exploitation likelihood.

Actively Exploited — CISA KEV

CVE-2026-20253: Splunk Enterprise Vulnerability

Severity: Unknown | CVSS 3.1: N/A | KEV Added: 2026-06-18

What is CVE-2026-20253?

Splunk Enterprise contains a missing authentication for critical function vulnerability which could allow an unauthenticated user to create or truncate arbitrary files through a PostgreSQL sidecar service endpoint.

Impact Analysis

Exploitation Probability (EPSS): 10.0% chance of exploitation in the next 30 days (95th percentile). This is a significantly elevated exploitation probability — prioritize patching.

Exploit Availability

Public exploit code or proof-of-concept is available for CVE-2026-20253. This significantly increases the risk of exploitation, as attackers can use or adapt existing exploit code rather than developing their own. A public exploit reference has been identified. Organizations should treat this as an urgent patching priority.

Is CVE-2026-20253 being exploited?

Yes. CVE-2026-20253 is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, restricted to CVEs with confirmed active exploitation in the wild. CISA added this vulnerability on 2026-06-18. Inclusion in KEV triggers the patching mandate under BOD 22-01 for U.S. federal civilian agencies, with a remediation deadline of 2026-06-21. Additionally, public exploit code is available, which lowers the barrier for attackers.

How to fix CVE-2026-20253

Apply the security update issued by Splunk for Enterprise. If an immediate patch is not possible, consult the vendor advisory for mitigation guidance, restrict network exposure of the affected service, and monitor logs for indicators of exploitation. CISA's Known Exploited Vulnerabilities catalog requires U.S. federal agencies to remediate this vulnerability by the due date shown below under Binding Operational Directive 22-01. Private organizations should treat KEV entries as priority-one patches because active exploitation has been confirmed in the wild.

Frequently asked questions

Is CVE-2026-20253 critical?

CVE-2026-20253 has a CVSS 3.1 base score of N/A — Unknown severity. Prioritize based on exposure and the active exploitation signal from the KEV listing. The availability of public exploit code further increases the urgency.

Is CVE-2026-20253 being actively exploited?

Yes — CISA added CVE-2026-20253 to the Known Exploited Vulnerabilities catalog on 2026-06-18. Inclusion in KEV means CISA has confirmed in-the-wild exploitation. Public exploit code has also been identified, making exploitation accessible to a broader range of threat actors.

How do I patch CVE-2026-20253?

Apply the security update from Splunk for Enterprise. Federal agencies must remediate by 2026-06-21 under BOD 22-01.

What is the CVSS score for CVE-2026-20253?

CVE-2026-20253 has a CVSS 3.1 base score of N/A, classifying it as Unknown severity.