CVE-2026-18736

Shlink contains a server-side request forgery vulnerability that allows authenticated API key holders to cause the server to issue arbitrary HTTP GET requests by supplying a crafted long URL during short URL creation with title auto-resolution enabled. Attackers can submit URLs pointing to public hosts that redirect to internal targets, including loopback addresses, link-local ranges, and cloud metadata endpoints such as 169.254.169.254, to exfiltrate internal service information via the HTML title element returned in the short URL creation response.

CVSS v3 5.0 MEDIUM

5.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.1 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/shlinkio/shlink
https://github.com/theopaid/Server-side-request-forgery-through-short-URL-title-resolution-shlink-
https://www.vulncheck.com/advisories/shlink-server-side-request-forgery-via-short-url-title-auto-resolution
https://github.com/theopaid/Server-side-request-forgery-through-short-URL-title-resolution-shlink-

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-03 21:16

Updated : 2026-09-09 20:35

NVD link : CVE-2026-18736

Mitre link : CVE-2026-18736

CVE.ORG link : CVE-2026-18736

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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