CVE-2026-18736 (GCVE-0-2026-18736)
Vulnerability from cvelistv5
Published
2026-08-03 20:15
Modified
2026-08-04 13:45
Severity ?
5.3 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N
5.0 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
CWE
  • CWE-918 - Server-Side Request Forgery (SSRF)
Summary
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.
References
Impacted products
Vendor Product Version
shlinkio Shlink Version: 2.6.0
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