EXECUTIVE SUMMARY:
CVE-2026-20253 with a CVSS score of 9.8 is a critical unauthenticated file‑operation flaw in Splunk Enterprise that affects versions 10.0.0‑10.0.6 and 10.2.0‑10.2.3 (any release below 10.0.7 or 10.2.4). The vulnerability resides in the PostgreSQL sidecar service endpoint, which lacks any authentication checks, allowing any network‑reachable user to call the “/v1/postgres/recovery/backup” and “/v1/postgres/recovery/restore” APIs. An attacker can craft a request that backs up an attacker‑controlled database to an arbitrary location on the Splunk host, then use the restore endpoint with a “passfile” argument pointing to the .pgpass file to load the dump, causing the embedded SQL to execute functions such as lo_export that write attacker‑controlled content to the filesystem. This gives the adversary an arbitrary file‑write primitive, which can be leveraged to overwrite a frequently executed Python script (e.g., ssg_enable_modular_input.py) and achieve remote code execution. Business impact includes full compromise of the Splunk monitoring platform, potential exfiltration of logs, disruption of security operations, and lateral movement within the network. Exploitation requires the sidecar endpoint to be reachable from the attacker’s network and the target to be running a vulnerable Splunk Enterprise version; Splunk Cloud is not affected because it does not use the sidecar service.[/subscribe_to_unlock_form]
EXECUTIVE SUMMARY:
CVE-2026-20253 with a CVSS score of 9.8 is a critical unauthenticated file‑operation flaw in Splunk Enterprise that affects versions 10.0.0‑10.0.6 and 10.2.0‑10.2.3 (any release below 10.0.7 or 10.2.4). The vulnerability resides in the PostgreSQL sidecar service endpoint, which lacks any authentication checks, allowing any network‑reachable user to call the “/v1/postgres/recovery/backup” and “/v1/postgres/recovery/restore” APIs. An attacker can craft a request that backs up an attacker‑controlled database to an arbitrary location on the Splunk host, then use the restore endpoint with a “passfile” argument pointing to the .pgpass file to load the dump, causing the embedded SQL to execute functions such as lo_export that write attacker‑controlled content to the filesystem. This gives the adversary an arbitrary file‑write primitive, which can be leveraged to overwrite a frequently executed Python script (e.g., ssg_enable_modular_input.py) and achieve remote code execution. Business impact includes full compromise of the Splunk monitoring platform, potential exfiltration of logs, disruption of security operations, and lateral movement within the network. Exploitation requires the sidecar endpoint to be reachable from the attacker’s network and the target to be running a vulnerable Splunk Enterprise version; Splunk Cloud is not affected because it does not use the sidecar service.[emaillocker id="1283"]
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REFERENCES:
The following reports contain further technical details:
https://thehackernews.com/2026/06/critical-splunk-enterprise-flaw-lets.html