{"id":"CVE-2026-18736","summary":"Shlink Server-Side Request Forgery via Short URL Title Auto-Resolution","details":"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.","modified":"2026-08-06T03:31:06.692094999Z","published":"2026-08-03T20:15:22.814Z","database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-918"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/18xxx/CVE-2026-18736.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/18xxx/CVE-2026-18736.json"},{"type":"ADVISORY","url":"https://github.com/theopaid/Server-side-request-forgery-through-short-URL-title-resolution-shlink-"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-18736"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/shlink-server-side-request-forgery-via-short-url-title-auto-resolution"},{"type":"PACKAGE","url":"https://github.com/shlinkio/shlink"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/shlinkio/shlink","events":[{"introduced":"3d99fc17081aa43463e715cf1e180abf47e12fb4"},{"last_affected":"c201760cccb84c61f70d16baca26e1e548eb1157"}],"database_specific":{"extracted_events":[{"introduced":"2.6.0"},{"last_affected":"5.1.5"}],"source":"AFFECTED_FIELD"}}],"versions":["v5.1.5","v5.1.4","v5.1.3","v5.1.2","v5.1.1","v5.1.0","v5.0.2","v5.0.1","v5.0.0","v4.6.0","v4.5.3","v4.5.2","v4.5.1","v4.5.0","v4.4.6","v4.4.5","v4.4.4","v4.4.3","v4.4.2","v4.4.1","v4.4.0","v4.3.1","v4.3.0","v4.2.5","v4.2.4","v4.2.3","v4.2.2","v4.2.1","v4.2.0","v4.1.1","v4.1.0","v4.0.3","v4.0.2","v3.7.3","v4.0.1","v4.0.0","v3.7.2","v3.7.1","v3.7.0","v3.6.4","v3.6.3","v3.6.2","v3.6.1","v3.6.0","v3.5.4","v3.5.3","v3.5.2","v3.5.1","v3.5.0","v3.4.0","v3.3.2","v3.3.1","v3.3.0","v3.2.1","v3.2.0","v3.1.2","v3.1.1","v3.1.0","v3.0.3","v3.0.2","v3.0.1","v3.0.0","v2.10.3","v2.10.2","v2.10.1","v2.10.0","v2.9.3","v2.9.2","v2.9.1","v2.9.0","v2.8.1","v2.8.0","v2.7.3","v2.7.2","v2.7.1","v2.7.0","v2.6.2","v2.6.1","v2.6.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-18736.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V4","score":"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"}]}