{ "schema_version": "1.4.0", "id": "GHSA-w7x5-g22v-xqhr", "modified": "2026-07-22T22:57:36Z", "published": "2026-07-22T22:57:36Z", "aliases": [ "CVE-2026-8384" ], "summary": "Eclipse Jetty: Path parameter traversal", "details": "### Description (as reported)\n\n#### Summary\n\nIn Jetty 12.1.8, org.eclipse.jetty.util.URIUtil.canonicalPath() may leave dot-dot path segments unnormalized when a semicolon path parameter marker is followed by a slash and a dot\n segment.\n\nA minimal example is:\n\n`/public;/../admin/secret`\n\nIn my local reproduction, URIUtil.canonicalPath() returns:\n\n`/public/../admin/secret`\n\ninstead of the expected normalized path:\n\n`/admin/secret`\n\nWhen Jetty's `SecurityHandler.PathMapped` is used to protect a path prefix such as `/admin/*`, the non-normalized canonical path may not match the protected prefix. As a result, an unauthenticated request may bypass the configured path-based security constraint.\n\n\n\n#### Tested Version\n\nJetty: 12.1.8\nJDK: 17.0.18\nMaven: 3.9.14\n\nMaven artifacts used:\n\n org.eclipse.jetty:jetty-server:12.1.8\n org.eclipse.jetty:jetty-security:12.1.8\n org.eclipse.jetty:jetty-session:12.1.8\n\nOnly confirmed Jetty 12.1.8 so far. \n\n\n#### Minimal Reproduction\n\nStarts a minimal Jetty server with the following security setup:\n\n```java\nSecurityHandler.PathMapped security = new SecurityHandler.PathMapped();\nsecurity.put(\"/admin/*\", Constraint.from(\"admin\"));\nsecurity.put(\"/*\", Constraint.ALLOWED);\nsecurity.setAuthenticator(new BasicAuthenticator());\n```\n\nThe test then sends requests with no `Authorization` header.\n\nObserved result:\n\n```\nGET /admin/secret -> 401\nGET /public;x/../admin/secret -> 200\n```\n\nThe handler receives paths such as:\n\n`/public/../admin/secret`\n\nThis suggests that the `/admin/*` security constraint is bypassed because `PathMapped` matching is performed against the non-normalized canonical path.\n\n\n#### Suspected Root Cause\n\nThe suspected root cause is in `URIUtil.canonicalPath()`.\n\nThe relevant logic is approximately:\n\n```java\n for (int i = 0; i < end; i++)\n {\n char c = encodedPath.charAt(i);\n\n switch (c)\n {\n case ';':\n if (builder == null)\n {\n builder = new Utf8StringBuilder(encodedPath.length());\n builder.append(encodedPath, 0, i);\n }\n\n while (++i < end)\n {\n if (encodedPath.charAt(i) == '/')\n {\n builder.append('/');\n break;\n }\n }\n break;\n\n case '.':\n if (slash)\n normal = false;\n if (builder != null)\n builder.append(c);\n break;\n }\n\n slash = c == '/';\n }\n\n String canonical = (builder != null)\n ? (onBadUtf8 == null ? builder.toCompleteString() : builder.takeCompleteString(onBadUtf8))\n : encodedPath;\n return normal ? canonical : normalizePath(canonical);\n```\n\nFor the input:\n\n`/public;/../admin/secret`\n\nwhen the outer loop reaches the semicolon:\n\n```\n i = 7\n c = ';'\n slash = false\n normal = true\n```\n\nInside `case ';'`, the `while (++i < end)` loop advances i to the next character, which is already '/' for the empty path parameter form \";/\".\n\nThe code then appends '/' to the canonical builder:\n\n`builder.append('/');`\n\nAt this point, the canonical builder ends with '/':\n\n`/public/`\n\nHowever, the local variable `c` is still the old value ';', because `c` was read before entering the switch and is not updated when the inner loop advances `i`.\n\nAfter leaving the switch, the loop updates the slash state using:\n\n`slash = c == '/';`\n\nSince `c` is still ';', slash becomes `false`.\n\nOn the next iteration, the scanner reaches '.', which is the first dot in the following \"../\" segment. Because slash is incorrectly `false`, this code does not run:\n\n```java\n if (slash)\n normal = false;\n```\n\nTherefore `normal` remains `true`, and `canonicalPath()` returns the canonical string directly instead of calling `normalizePath(canonical)`.\n\nThe result is:\n\n`/public/../admin/secret`\n\ninstead of:\n\n`/admin/secret`\n\nIn short:\n\n`case ';'` advances the scan position i and appends '/' to the canonical builder, but the loop tail still updates slash from the stale character `c=';'`. As a result, the following dot-dot segment is not detected as a path traversal segment.\n\n#### More Precise Trigger Condition\n\nThe issue is not limited to a non-empty path parameter such as \";x\".\n\nThe more precise trigger shape is:\n\n`;[^/]*/.`\n\nExamples:\n\n```\n /public;/../admin/secret\n /public;x/../admin/secret\n /public;anything/../admin/secret\n /public;/./admin/secret\n```\n\nThe minimal form is:\n\n`/public;/../admin/secret`\n\nbecause the semicolon is immediately followed by '/', so the inner while loop reaches '/' on its first increment.\n\n#### Potential Minimal Fix Direction\n\nA minimal fix would be to ensure that, when case ';' consumes input until '/' and appends '/' to the canonical builder, the slash state reflects the last effective character in the canonical path.\n\nFor example, conceptually:\n\n```java\n case ';':\n if (builder == null)\n {\n builder = new Utf8StringBuilder(encodedPath.length());\n builder.append(encodedPath, 0, i);\n }\n\n while (++i < end)\n {\n if (encodedPath.charAt(i) == '/')\n {\n builder.append('/');\n slash = true;\n break;\n }\n }\n continue;\n```\n\nThe important part is to avoid the loop tail from overwriting slash using the stale `c` value:\n\n`slash = c == '/';`\n\nIn other words, `slash` should represent the last effective character appended to the canonical builder, not the original input character read before case ';' advanced `i`.", "severity": [ { "type": "CVSS_V3", "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N" } ], "affected": [ { "package": { "ecosystem": "Maven", "name": "org.eclipse.jetty:jetty-util" }, "ranges": [ { "type": "ECOSYSTEM", "events": [ { "introduced": "12.0.0" }, { "fixed": "12.0.35" } ] } ], "database_specific": { "last_known_affected_version_range": "<= 12.0.34" } }, { "package": { "ecosystem": "Maven", "name": "org.eclipse.jetty:jetty-util" }, "ranges": [ { "type": "ECOSYSTEM", "events": [ { "introduced": "12.1.0" }, { "fixed": "12.1.9" } ] } ], "database_specific": { "last_known_affected_version_range": "<= 12.1.8" } } ], "references": [ { "type": "WEB", "url": "https://github.com/jetty/jetty.project/security/advisories/GHSA-w7x5-g22v-xqhr" }, { "type": "ADVISORY", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-8384" }, { "type": "WEB", "url": "https://github.com/jetty/jetty.project/pull/14969" }, { "type": "WEB", "url": "https://github.com/jetty/jetty.project/pull/14973" }, { "type": "WEB", "url": "https://github.com/jetty/jetty.project/commit/82969c77f6da46e27008b10b3c14840cd31db084" }, { "type": "WEB", "url": "https://github.com/jetty/jetty.project/commit/ade27ce93a37c33278720250d85c48601230ae3f" }, { "type": "PACKAGE", "url": "https://github.com/jetty/jetty.project" }, { "type": "WEB", "url": "https://github.com/jetty/jetty.project/releases/tag/jetty-12.0.35" }, { "type": "WEB", "url": "https://github.com/jetty/jetty.project/releases/tag/jetty-12.1.9" }, { "type": "WEB", "url": "https://gitlab.eclipse.org/security/cve-assignment/-/work_items/108" } ], "database_specific": { "cwe_ids": [ "CWE-647" ], "severity": "MODERATE", "github_reviewed": true, "github_reviewed_at": "2026-07-22T22:57:36Z", "nvd_published_at": "2026-07-14T09:16:42Z" } }