{"id":"CVE-2026-20253","aliases":["EUVD-2026-36088","GHSA-xgm5-jh99-wc4v"],"status":"published","title":"Unauthenticated Arbitrary File Creation and Truncation in a PostgreSQL Sidecar Service Endpoint in Splunk Enterprise","description":"In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint. The vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials. Splunk Enterprise versions 9.4 and earlier are not affected. If you cannot immediately upgrade to a fixed version, you can mitigate this vulnerability by disabling the PostgreSQL sidecar service.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.96939,"percentile":0.99889,"model":"v2026.06.15"},"facts":{"in_kev":true,"known_exploited":true,"public_exploit":true,"fix_available":false},"cwes":["CWE-306"],"published":"2026-06-10T17:16:21Z","modified":"2026-07-23T09:10:00Z","kev":{"date_added":"2026-06-18","due_date":"2026-06-21","required_action":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","known_ransomware_use":"Unknown"},"exploitation":[{"source":"euvd","since":"2026-06-18"},{"source":"kev","since":"2026-06-18"}],"exploits":[{"source":"pocgithub","id":"watchtowrlabs/watchTowr-vs-Splunk-CVE-2026-20253","title":"watchtowrlabs/watchTowr-vs-Splunk-CVE-2026-20253","date":"2026-06-12","url":"https://github.com/watchtowrlabs/watchTowr-vs-Splunk-CVE-2026-20253"},{"source":"pocgithub","id":"ashrafzaryouh/CVE-2026-20253","title":"ashrafzaryouh/CVE-2026-20253","date":"2026-06-13","url":"https://github.com/ashrafzaryouh/CVE-2026-20253"},{"source":"pocgithub","id":"HORKimhab/CVE-2026-20253","title":"HORKimhab/CVE-2026-20253","date":"2026-06-14","url":"https://github.com/HORKimhab/CVE-2026-20253"},{"source":"pocgithub","id":"fevar54/CVE-2026-20253-Splunk-Enterprise-Pre-Auth-RCE-","title":"fevar54/CVE-2026-20253-Splunk-Enterprise-Pre-Auth-RCE-","date":"2026-06-26","url":"https://github.com/fevar54/CVE-2026-20253-Splunk-Enterprise-Pre-Auth-RCE-"},{"source":"pocgithub","id":"pssec-io/CVE-2026-20253","title":"pssec-io/CVE-2026-20253","date":"2026-06-29","url":"https://github.com/pssec-io/CVE-2026-20253"},{"source":"pocgithub","id":"Het-Kalariya/CVE-2026-20253","title":"Het-Kalariya/CVE-2026-20253","date":"2026-07-18","url":"https://github.com/Het-Kalariya/CVE-2026-20253"},{"source":"pocgithub","id":"NSK-394/owasp-nettacker-contribution","title":"NSK-394/owasp-nettacker-contribution","date":"2026-07-18","url":"https://github.com/NSK-394/owasp-nettacker-contribution"},{"source":"pocgithub","id":"ivanesk315/CVE-2026-20253","title":"ivanesk315/CVE-2026-20253","date":"2026-09-10","url":"https://github.com/ivanesk315/CVE-2026-20253"},{"source":"nuclei","id":"CVE-2026-20253","title":"Splunk Enterprise \u0026 Cloud Platform - Unrestricted File Upload","type":"detection template","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-20253.yaml"}],"products":[{"vendor":"splunk","product":"enterprise"},{"vendor":"splunk","product":"splunk"},{"vendor":"splunk","product":"splunk enterprise"}],"references":[{"url":"https://advisory.splunk.com/advisories/SVD-2026-0603","tags":["Mitigation","Vendor Advisory"]},{"url":"https://labs.watchtowr.com/why-use-app-level-auth-when-every-database-has-auth-splunk-enterprise-cve-2026-20253-pre-auth-rce/","tags":["exploit","Exploit","Third Party Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20253","tags":["government-resource","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-20253"},{"url":"https://labs.watchtowr.com/why-use-app-level-auth-when-every-database-has-auth-splunk-enterprise-cve-2026-20253-pre-auth-rce"},{"url":"https://github.com/advisories/GHSA-xgm5-jh99-wc4v"}],"sources":{"cve":[{"id":"CVE-2026-20253","title":"Unauthenticated Arbitrary File Creation and Truncation in a PostgreSQL Sidecar Service Endpoint in Splunk Enterprise","description":"In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint. The vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials. Splunk Enterprise versions 9.4 and earlier are not affected. If you cannot immediately upgrade to a fixed version, you can mitigate this vulnerability by disabling the PostgreSQL sidecar service.","status":"published","published":"2026-06-10T17:16:21.242Z","modified":"2026-06-19T03:55:19.206Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T13:35:55.731353Z"}],"euvd":[{"id":"EUVD-2026-36088","description":"In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint. The vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials. Splunk Enterprise versions 9.4 and earlier are not affected. If you cannot immediately upgrade to a fixed version, you can mitigate this vulnerability by disabling the PostgreSQL sidecar service.","status":"published","published":"2026-06-10T17:16:21Z","modified":"2026-06-19T03:55:19Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"exploited_since":"2026-06-18","updated_at":"2026-11-02T18:20:36.276608Z"}],"ghsa":[{"id":"GHSA-xgm5-jh99-wc4v","title":"In Splunk Enterprise versions below 10.2.4 and 10.0.7, and Splunk Cloud Platform versions below...","description":"In Splunk Enterprise versions below 10.2.4 and 10.0.7, and Splunk Cloud Platform versions below 10.4.2604.3 and 10.2.2510.14, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint.\u003cbr\u003e\u003cbr\u003eThe vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials.","status":"published","published":"2026-06-10T18:31:46Z","modified":"2026-06-18T18:35:18Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T15:08:53.737891Z"}],"kev":[{"id":"CVE-2026-20253","title":"Splunk Enterprise Missing Authentication for Critical Function Vulnerability","description":"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.","cwes":["CWE-306"],"kev":{"date_added":"2026-06-18","due_date":"2026-06-21","required_action":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","known_ransomware_use":"Unknown"},"updated_at":"2026-11-02T17:00:15.999436Z"}],"nvd":[{"id":"CVE-2026-20253","description":"In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint. The vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials. Splunk Enterprise versions 9.4 and earlier are not affected. If you cannot immediately upgrade to a fixed version, you can mitigate this vulnerability by disabling the PostgreSQL sidecar service.","status":"published","published":"2026-06-10T18:16:40.76Z","modified":"2026-07-23T09:10:00.113Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"secondary"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T14:12:23.485267Z"}]}}