GHSA-f25v-x6vr-962g: Pheditor Authentication Bypass Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-f25v-x6vr-962g",
  "modified" : "2026-07-24T21:54:24Z",
  "published" : "2026-07-24T21:54:24Z",
  "aliases" : [ ],
  "summary" : "Pheditor: Authentication Bypass in Forced Password-Change Flow via Unverified Current Password",
  "details" : "## Summary\n\nThe forced password-change flow, triggered when the stored password is still the default (`admin`), does not verify that the password submitted by the client actually matches the current password. Any non-empty value in `pheditor_password` is enough to reach the password-change form, and submitting `pheditor_new_password` / `pheditor_confirm_password` in the same request is enough to set an arbitrary new password and obtain an authenticated session — without ever proving knowledge of the current password.\n\n## Root Cause\n\n`pheditor.php` line 163:\n\n```php\nif (PASSWORD == hash('sha512', 'admin')) { // still default — force change prompt\n```\n\nThis checks whether the **stored** `PASSWORD` constant is still the default value. It does not check whether the **submitted** `pheditor_password` matches it. As a result, on any instance that hasn't changed the default password, the check passes regardless of what the client actually sends, and the subsequent password-change branch is reachable without authentication.\n\n## PoC\n\n```bash\nTARGET=\"https://victim.com/pheditor.php\"\n\n# Any non-empty value works here — password is never actually verified\ncurl -c /tmp/j.txt \\\n  -d 'pheditor_password=anything' \\\n  -d 'pheditor_new_password=attacker123' \\\n  -d 'pheditor_confirm_password=attacker123' \\\n  \"$TARGET\" -L -s -o /dev/null\n\n# Session is now authenticated as admin, with the password changed to attacker123\n```\n\n## Impact\n\nOn any instance where the default password has not yet been changed, an unauthenticated attacker can set an arbitrary new admin password and obtain a fully authenticated session, without knowing the current password. This is a complete authentication bypass, not merely \"default credentials in use\" — it holds even if the operator believes the instance is protected because the login form is present.\n\n## Remediation\n\nVerify the submitted password against the stored `PASSWORD` constant *before* entering the forced password-change branch, so the flow is reachable only by someone who actually knows the current password:\n\n```php\n$submitted_hash = hash('sha512', $_POST['pheditor_password']);\n\nif (PASSWORD == hash('sha512', 'admin') && $submitted_hash === PASSWORD) {\n    // proceed to forced password-change flow\n} else {\n    // treat as a normal login attempt (including rate-limiting)\n}\n```\n\n## Note on scope\n\nThe original report submitted alongside this finding also included two additional items:\n\n- **Unrestricted PHP upload** — addressed as intended behavior (Pheditor is a single-admin PHP file editor; PHP file creation/editing is core to its function, and pattern-restricting only the upload path doesn't reduce risk since the same result is reachable via the `save`/`newfile` action). Documented explicitly in the README's new Security Model section.\n- **Terminal allowlist bypass (`php -r ...`)** — a duplicate of a previously reported and already-patched issue (GHSA-g3hq-hphg-8fhh, fixed in v2.0.7).\n\nThis advisory has been scoped to the authentication bypass specifically, since it's a distinct root cause from both of those. Full responses to all three points are in the comments below.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "pheditor/pheditor"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.0.8"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/pheditor/pheditor/security/advisories/GHSA-f25v-x6vr-962g"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pheditor/pheditor/commit/0978bcda644832b67357340e2f271e32d86fdf86"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/pheditor/pheditor"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pheditor/pheditor/releases/tag/2.0.8"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-1392" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-24T21:54:24Z",
    "nvd_published_at" : null
  }
}