CVE-2026-18736

EUVD-2026-52427
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.
SSRF
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
References
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