CVE-2025-1521: PostHog slack_incoming_webhook Server-Side Request Forgery Information Disclosure Vulnerability

Published Apr 23, 2025
·
Updated

PostHog slackincomingwebhook Server-Side Request Forgery Information Disclosure Vulnerability. This vulnerability allows remote attackers to disclose sensitive information on affected installations of PostHog. Authentication is required to exploit this vulnerability.

The specific flaw exists within the processing of the slackincomingwebhook parameter. The issue results from the lack of proper validation of a URI prior to accessing resources. An attacker can leverage this vulnerability to execute code in the context of the service account. Was ZDI-CAN-25352.

Affected Software

2 affected components
PostHog PostHog
PostHog PostHog<0.3.7

Remediation

Patch Available

https://github.com/PostHog/posthog/commit/6e8f035f9acd339c5ba87ba6ea40fc1ab3053d42

Event History

Apr 23, 2025
CVE Published
via MITRE·04:45 PM
Data Sourced
via MITRE·04:45 PM
DescriptionSeverityWeakness
Advisory Published
via ZDI·05:03 PM
Data Sourced
via NVD·05:16 PM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2025-1521?

CVE-2025-1521 is classified as a medium severity vulnerability.

2

What type of vulnerability is CVE-2025-1521?

CVE-2025-1521 is a Server-Side Request Forgery (SSRF) vulnerability.

3

How do I fix CVE-2025-1521?

To fix CVE-2025-1521, update to the latest version of PostHog that addresses the vulnerability.

4

Who is affected by CVE-2025-1521?

CVE-2025-1521 affects installations of PostHog that have the slack_incoming_webhook feature enabled.

5

What can attackers do with CVE-2025-1521?

Attackers can exploit CVE-2025-1521 to disclose sensitive information from affected PostHog installations.

Company

Resources

Contact

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