{"id":"GHSA-8fp4-rp6c-5gcv","summary":"Path Traversal in com.linecorp.armeria:armeria","details":"### Impact\n\nAn attacker can access an Armeria server's local file system beyond its restricted directory by sending an HTTP request whose path contains `%2F` (encoded `/`), such as `/files/..%2Fsecrets.txt`, bypassing Armeria's path validation logic.\n\n### Patches\n\nArmeria 1.13.4 or above contains the hardened path validation logic that handles `%2F` properly. \n\n### Workarounds\n\nThis vulnerability can be worked around by inserting a decorator that performs an additional validation on the request path, e.g.\n\n```java\nServer\n  .builder()\n  .serviceUnder(\n    \"/files\",\n    FileService\n      .of(...)\n      .decorate((delegate, ctx, req) -\u003e {\n        String path = req.headers().path();\n        if (path.contains(\"%2f\") || path.contains(\"%2F\")) {\n          return HttpResponse.of(HttpStatus.BAD_REQUEST);\n        }\n        return delegate.serve(ctx, req);\n      })\n  )\n  .build()\n```\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n* Open an issue in [line/armeria](https://github.com/line/armeria)\n* Chat with us at [Slack](https://armeria.dev/s/slack)\n\n### Credits\n\nThis vulnerability was originally reported by Abdallah Zaher ([elcayser-0x0a](https://hackerone.com/elcayser-0x0a?type=user)).","aliases":["CVE-2021-43795"],"modified":"2026-07-08T06:28:32.358987072Z","published":"2021-12-02T22:25:54Z","database_specific":{"github_reviewed_at":"2021-12-02T21:28:29Z","nvd_published_at":"2021-12-02T18:15:00Z","cwe_ids":["CWE-22"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/line/armeria/security/advisories/GHSA-8fp4-rp6c-5gcv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-43795"},{"type":"WEB","url":"https://github.com/line/armeria/pull/3855"},{"type":"WEB","url":"https://github.com/line/armeria/commit/e2697a575e9df6692b423e02d731f293c1313284"},{"type":"PACKAGE","url":"https://github.com/line/armeria"}],"affected":[{"package":{"name":"com.linecorp.armeria:armeria","ecosystem":"Maven","purl":"pkg:maven/com.linecorp.armeria/armeria"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.12.0"},{"fixed":"1.13.4"}]}],"versions":["1.12.0","1.13.0","1.13.1","1.13.2","1.13.3"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/12/GHSA-8fp4-rp6c-5gcv/GHSA-8fp4-rp6c-5gcv.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"}]}