CVE-2026-73629: Server-Side Request Forgery (SSRF) in s9y Serendipity
Serendipity versions before 2.6.0 contain a server-side request forgery (SSRF) vulnerability in the serendipity_url_allowed() filter. This filter fails to block certain alternate IP address formats, including hex-encoded IPv4, IPv6 literals, and link-local ranges. Authenticated users with adminImagesAdd permission can exploit this to bypass the filter and make requests to internal services, retrieving response bodies via the public uploads directory.
AI Analysis
Technical Summary
CVE-2026-73629 is a server-side request forgery vulnerability affecting Serendipity before version 2.6.0. The vulnerability exists in the serendipity_url_allowed() filter, which does not properly block hex-encoded IPv4 addresses, IPv6 literals, and link-local IP ranges. An authenticated user with adminImagesAdd permission can exploit this flaw by using alternate address formats to bypass the filter, enabling them to send requests to internal services and retrieve the responses through the public uploads directory.
Potential Impact
An attacker with authenticated access and adminImagesAdd permission can abuse this vulnerability to perform SSRF attacks, potentially accessing internal services that are not otherwise exposed. This could lead to unauthorized information disclosure from internal network resources. The vulnerability has a high severity score (CVSS 8.4) reflecting the potential impact on confidentiality and integrity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict or review permissions for users with adminImagesAdd rights and monitor for suspicious activity related to internal service access via the uploads directory.
CVE-2026-73629: Server-Side Request Forgery (SSRF) in s9y Serendipity
Description
Serendipity versions before 2.6.0 contain a server-side request forgery (SSRF) vulnerability in the serendipity_url_allowed() filter. This filter fails to block certain alternate IP address formats, including hex-encoded IPv4, IPv6 literals, and link-local ranges. Authenticated users with adminImagesAdd permission can exploit this to bypass the filter and make requests to internal services, retrieving response bodies via the public uploads directory.
CVSS v4.0
Score 8.4high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-73629 is a server-side request forgery vulnerability affecting Serendipity before version 2.6.0. The vulnerability exists in the serendipity_url_allowed() filter, which does not properly block hex-encoded IPv4 addresses, IPv6 literals, and link-local IP ranges. An authenticated user with adminImagesAdd permission can exploit this flaw by using alternate address formats to bypass the filter, enabling them to send requests to internal services and retrieve the responses through the public uploads directory.
Potential Impact
An attacker with authenticated access and adminImagesAdd permission can abuse this vulnerability to perform SSRF attacks, potentially accessing internal services that are not otherwise exposed. This could lead to unauthorized information disclosure from internal network resources. The vulnerability has a high severity score (CVSS 8.4) reflecting the potential impact on confidentiality and integrity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict or review permissions for users with adminImagesAdd rights and monitor for suspicious activity related to internal service access via the uploads directory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-08-13T11:17:25.161Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a7dbdfdbf8831d5393226d5
Added to database: 08/13/2026, 12:52:13 UTC
Last enriched: 08/13/2026, 12:57:27 UTC
Last updated: 08/13/2026, 21:43:06 UTC
Views: 14
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