CVE-2025-1522 is a Server-Side Request Forgery (SSRF) vulnerability identified in the PostHog analytics platform, specifically within the implementation of the database_schema method. SSRF vulnerabilities occur when an attacker can manipulate a server to make unintended requests to internal or external resources. In this case, the vulnerability arises due to insufficient validation of URIs before the server accesses them. An authenticated attacker can exploit this flaw to coerce the PostHog server into sending requests to arbitrary URIs, potentially disclosing sensitive information accessible to the service account under which PostHog operates. This could include internal network resources or metadata services that are normally inaccessible externally. The vulnerability requires authentication, limiting exploitation to users with valid credentials, but once exploited, it can lead to information disclosure that may aid further attacks or reconnaissance. No public exploits are currently known, and no patches have been linked yet. The vulnerability was reserved and published in early 2025 and is tracked under CWE-918, which covers SSRF weaknesses. The affected version is identified by a specific commit hash, indicating a particular build or release of PostHog is vulnerable. The lack of proper URI validation in the database_schema method is the root cause, highlighting a need for improved input sanitization and request handling within the affected component.

For European organizations using PostHog, this vulnerability poses a moderate risk primarily related to confidentiality. Since PostHog is an analytics platform often integrated into web applications and internal dashboards, exploitation could allow attackers with valid credentials to access sensitive internal endpoints or metadata services, potentially exposing internal network structure, credentials, or other confidential data. This could facilitate lateral movement or further compromise within the organization. The requirement for authentication reduces the risk of widespread exploitation but does not eliminate insider threats or risks from compromised accounts. The integrity and availability of PostHog services are less likely to be directly impacted by this vulnerability. However, information disclosure can have significant consequences, especially for organizations handling sensitive user data or operating in regulated sectors such as finance, healthcare, or government. Additionally, attackers could leverage disclosed information to craft more targeted attacks. Given PostHog's growing adoption in Europe, particularly among tech companies and digital service providers, the vulnerability could affect a broad range of sectors. The absence of known exploits in the wild suggests limited immediate risk but underscores the importance of timely remediation to prevent future attacks.

1. Immediate mitigation should focus on restricting access to PostHog instances to trusted and authenticated users only, enforcing strong authentication mechanisms such as multi-factor authentication (MFA) to reduce the risk of credential compromise. 2. Network segmentation should be employed to limit PostHog's ability to access sensitive internal resources, minimizing the potential impact of SSRF exploitation. 3. Organizations should monitor and audit PostHog logs for unusual request patterns or access to unexpected internal URIs that may indicate exploitation attempts. 4. Although no official patch is currently linked, organizations should track PostHog vendor advisories closely and apply security updates or patches as soon as they become available. 5. Implement input validation and URI whitelisting at the application or proxy level to prevent PostHog from making requests to unauthorized or sensitive internal endpoints. 6. Conduct internal security assessments and penetration tests focusing on SSRF vectors within PostHog deployments to identify and remediate potential exploitation paths. 7. Educate administrators and users with access to PostHog about the risks of SSRF and the importance of safeguarding credentials and access controls.