{"cve":"CVE-2026-82731","nvd":{"published":"2026-09-01T03:16:52.993","modified":"2026-09-01T21:15:00.147","status":"Deferred","description":"URL Redirection to Untrusted Site ('Open Redirect') vulnerability in ash-project ash_typescript allows an attacker who controls a path-parameter value to redirect a generated client's request, and the credentials attached to it, to an unintended route or an external origin.\n\nThe URL builders in lib/ash_typescript/typed_controller/codegen/route_renderer.ex replace each :param placeholder with a bare template interpolation and never call encodeURIComponent, so the value reaches executeTypedControllerRequest raw. A value containing ../ is normalised away by the fetch URL resolver and reaches a different route, while ? or # truncates the path and can smuggle or override query parameters. For a route whose path begins with a parameter, a value such as /evil.example.com/x yields the protocol-relative URL //evil.example.com/x, sending the request and the credentials from TypedControllerConfig to an attacker-controlled host. Nothing constrains the value at runtime: get_path_param_type/2 emits only a TypeScript type, which is erased.\n\nThe query-string path is unaffected, since URLSearchParams.set encodes its own values.\n\nThis issue affects ash_typescript: from 0.15.0 before 0.18.0.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N","score":2.3},"cvss_v3":null,"cwes":["CWE-601"],"references":["https://cna.erlef.org/cves/CVE-2026-82731.html","https://github.com/ash-project/ash_typescript/commit/5165f752f5f92b755d946f2d1ce750ff69083ffc","https://github.com/ash-project/ash_typescript/security/advisories/GHSA-6g23-p936-fm2f","https://osv.dev/vulnerability/EEF-CVE-2026-82731","https://github.com/ash-project/ash_typescript/security/advisories/GHSA-6g23-p936-fm2f"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:50:50.842544443+00:00"},"epss":{"cve":"CVE-2026-82731","score":0.005,"percentile":0.42875,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}