{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.0.4"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "pheditor/pheditor"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.0.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-54540"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-78"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-16T20:01:05Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\n\nPheditor 2.0.4 has an authenticated terminal command whitelist bypass.\n\nThe terminal feature checks whether the submitted command starts with one of the configured `TERMINAL_COMMANDS` values, then passes the full command string to `shell_exec()`. Shell command substitution such as `$()` is not blocked, so an authenticated user with the `terminal` permission can bypass a restricted command allowlist and execute arbitrary shell commands as the web server user.\n\n### Details\n\nTested repository:\n\nhttps://github.com/pheditor/pheditor\n\nTested commit:\n\n`62b43df7cb8956a9b0deb9bec278ca8676c890c5`\n\nAffected version:\n\nPheditor 2.0.4\n\nRelevant code in `pheditor.php`:\n\n- The terminal handler receives `$_POST[\u0027command\u0027]` and stores it in `$command`.\n- It blocks only `\u0026`, `;`, and `||`.\n- It checks whether `$command` starts with one of the configured values in `TERMINAL_COMMANDS`.\n- It then passes the full command string to `shell_exec()`.\n\nRelevant logic:\n\n```php\n$command = $_POST[\u0027command\u0027];\n\nif (strpos($command, \u0027\u0026\u0027) !== false || strpos($command, \u0027;\u0027) !== false || strpos($command, \u0027||\u0027) !== false) {\n    echo json_error(\"Illegal character(s) in command (\u0026 ; ||)\\n\");\n    exit;\n}\n\nforeach ($terminal_commands as $value) {\n    $value = trim($value);\n\n    if (strlen($command) \u003e= strlen($value) \u0026\u0026 substr($command, 0, strlen($value)) == $value) {\n        $command_found = true;\n        break;\n    }\n}\n\n$output = shell_exec((empty($dir) ? null : \u0027cd \u0027 . escapeshellarg($dir) . \u0027 \u0026\u0026 \u0027) . $command . \u0027 \u0026\u0026 echo \\ ; pwd\u0027);\n```\n\nBecause the whitelist check is prefix-based and the full command is executed by a shell, a command such as `ls$(...)` passes when `ls` is allowed, while the command substitution is still executed by the shell.\n\n### PoC\n\nThis was reproduced locally with Docker and PHP 8.3.\n\nFor a strict test, the configured command allowlist was changed to only allow `ls`:\n\n```php\ndefine(\u0027TERMINAL_COMMANDS\u0027, \u0027ls\u0027);\n```\n\nControl request:\n\n```text\ncommand=whoami\n```\n\nObserved result:\n\n```text\nCommand not allowed\nAvailable commands:\nls\n```\n\nBypass request:\n\n```text\ncommand=ls$(printf pheditor-terminal-bypass \u003e/lab/app/site/proof.txt)\n```\n\nObserved result:\n\n```text\nproof.txt is created with the content:\npheditor-terminal-bypass\n```\n\nThis shows that even when only `ls` is allowed, arbitrary shell commands can still be executed through command substitution.\n\n### Impact\n\nAn authenticated user with the `terminal` permission can bypass the intended `TERMINAL_COMMANDS` restriction and execute arbitrary shell commands as the web server user.\n\nThis affects deployments where administrators rely on `TERMINAL_COMMANDS` to restrict terminal access to a small set of safe commands.\n\nSuggested fixes:\n\n- Avoid passing user-controlled command strings to `shell_exec()`.\n- Parse the command into executable and arguments.\n- Require an exact command name match instead of prefix matching.\n- Execute without a shell, for example with an argument-array based process API.\n- If shell execution remains necessary, reject shell metacharacters comprehensively, including command substitution syntax.\n- Consider disabling the terminal feature by default.\n\nReporter credit requested:\n\nshanjijian \u003cshanjijian@gmail.com\u003e",
  "id": "GHSA-9643-6xjp-vx57",
  "modified": "2026-07-16T20:01:05Z",
  "published": "2026-07-16T20:01:05Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pheditor/pheditor/security/advisories/GHSA-9643-6xjp-vx57"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pheditor/pheditor"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pheditor/pheditor/releases/tag/2.0.5"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Pheditor has an authenticated terminal command whitelist bypass"
}