PostHog slack_incoming_webhook server-side request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.5$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in PostHog. The affected element is the function slack_incoming_webhook. The manipulation leads to server-side request forgery. This vulnerability is listed as CVE-2025-1521. The attack may be initiated remotely. There is no available exploit. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in PostHog (affected version not known) and classified as critical. This issue affects the function slack_incoming_webhook. The manipulation with an unknown input leads to a server-side request forgery vulnerability. Using CWE to declare the problem leads to CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

PostHog slack_incoming_webhook 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 slack_incoming_webhook 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.

The advisory is shared at zerodayinitiative.com. The identification of this vulnerability is CVE-2025-1521 since 02/20/2025. The exploitation is known to be easy. The attack may be initiated remotely. Technical details are known, but no exploit is available.

Applying a patch is able to eliminate this problem.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.5

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 7.1
CNA Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Timelineinfo

02/20/2025 🔍
02/25/2025 +5 days 🔍
02/25/2025 +0 days 🔍
08/08/2025 +164 days 🔍

Sourcesinfo

Advisory: zerodayinitiative.com
Status: Confirmed

CVE: CVE-2025-1521 (🔍)
GCVE (CVE): GCVE-0-2025-1521
GCVE (VulDB): GCVE-100-296753

Entryinfo

Created: 02/25/2025 15:36
Updated: 08/08/2025 05:56
Changes: 02/25/2025 15:36 (50), 08/08/2025 05:56 (22)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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