Admidio writes session IDs and auto-login cookie values to application logs

Summary

When debug logging is enabled, Session::setCookie() logs full cookie values and Session::start() logs the current session ID. In a real Admidio deployment this includes both the active session cookie and the persistent auto-login cookie. Anyone with access to the log sink can recover live bearer-style credentials from the logs.

Vulnerable Code Links

• https://github.com/Admidio/admidio/blob/v5.0.9/src/Session/Entity/Session.php#L533-L540
• https://github.com/Admidio/admidio/blob/v5.0.9/src/Session/Entity/Session.php#L615-L617

Vulnerable Code

// src/Session/Entity/Session.php
$gLogger->info('Set Cookie!', array(
'name' => $name,
'value' => $value,
'expire' => $expire,
'path' => $path,
'domain' => $domain,
'secure' => $secure,
'httpOnly' => $httpOnly,
'sameSite' => 'lax'
));
...
session_start();
$gLogger->info('Session Started!', array(
'name' => $sessionName,
'limit' => $limit,
'path' => $path,
'domain' => $domain,
'secure' => $secure,
'httpOnly' => $httpOnly,
'sameSite' => 'lax',
'sessionId' => session_id()
));

What Does The Code Mean

Every time Admidio sets a cookie, it writes the raw cookie value to the application log. When a session starts, it writes the active session identifier too.

Why The Code Is Vulnerable

Session IDs and persistent auto-login values are credentials. Logging them turns the log file into a credential store and expands the trust boundary to anyone who can read logs, backups, or external log aggregation outputs.

Verification Environment

• Application: Admidio v5.0.9
• Runtime: Dockerized Admidio + MariaDB on http://localhost:18080
• Validation mode: real deployed application, not isolated unit tests

Steps To Reproduce

1. Enable Admidio debug logging.
2. Log in with auto_login=1 enabled.
3. Inspect the generated application log.
4. Observe that the log contains both the ADMIDIO_*_AUTO_LOGIN_ID value and the ADMIDIO_*_SESSION_ID value in cleartext.

PoC Script

from helpers import login, new_session, save_json


def main():
session = new_session()
result = login(session, "admin", "AdminPass123!", auto_login=True)
save_json("session_logging_login.json", result)


if __name__ == "__main__":
main()

PoC Output

{
  "cookies": {
"ADMIDIO_admidio_adm_AUTO_LOGIN_ID": "2%3AnO2BhCdRgFUMKT46e2EzS79Inf4oWiLWzLnX9Ko5",
"ADMIDIO_admidio_adm_SESSION_ID": "iga3ujr67cti6s7btnuhecte67"
  },
  "csrf": "y41CaDdEO7RKug5FIRWO2Dx8w7KVQZ",
  "json": {
"status": "success",
"url": "http://localhost:18080/modules/overview.php"
  },
  "status_code": 200
}

5191:[2026-04-30 20:57:59.555213] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"8224iqk8aqcsb0062d0c3f1ish"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
5291:[2026-04-30 20:57:59.575756] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"8224iqk8aqcsb0062d0c3f1ish"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
5480:[2026-04-30 20:57:59.623872] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"733jf4j6po8m6b1g7glgaghfsg"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
5624:[2026-04-30 20:57:59.663760] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"733jf4j6po8m6b1g7glgaghfsg"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
5655:[2026-04-30 20:57:59.788831] Admidio.INFO: Set Cookie! {"name":"ADMIDIO_admidio_adm_SESSION_ID","value":"ovnk3hhpj5829dj63pjk4i7k8b","expire":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":533,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"setCookie"}
5680:[2026-04-30 20:57:59.795443] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"ovnk3hhpj5829dj63pjk4i7k8b"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
5815:[2026-04-30 20:57:59.838697] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"ovnk3hhpj5829dj63pjk4i7k8b"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
5839:[2026-04-30 20:58:09.374182] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"dvrl2qf92skdeimh77ruglr4ga"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
5983:[2026-04-30 20:58:09.423217] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"dvrl2qf92skdeimh77ruglr4ga"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6014:[2026-04-30 20:58:09.550875] Admidio.INFO: Set Cookie! {"name":"ADMIDIO_admidio_adm_SESSION_ID","value":"2th9qe9etfiis6nujdqpkfd9hv","expire":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":533,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"setCookie"}
6039:[2026-04-30 20:58:09.557823] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"2th9qe9etfiis6nujdqpkfd9hv"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6273:[2026-04-30 20:58:19.171185] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"k50i1toh4491o6v0htliv2kafs"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6417:[2026-04-30 20:58:19.212351] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"k50i1toh4491o6v0htliv2kafs"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6448:[2026-04-30 20:58:19.337758] Admidio.INFO: Set Cookie! {"name":"ADMIDIO_admidio_adm_SESSION_ID","value":"4emiuth6i2fc1ho17nahf6n52g","expire":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":533,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"setCookie"}
6473:[2026-04-30 20:58:19.346804] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"4emiuth6i2fc1ho17nahf6n52g"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6605:[2026-04-30 20:58:19.390909] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"4emiuth6i2fc1ho17nahf6n52g"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6635:[2026-04-30 20:58:19.409216] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"4emiuth6i2fc1ho17nahf6n52g"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6676:[2026-04-30 20:58:31.002317] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"aegildsksa0i5184igdk12pdg3"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6820:[2026-04-30 20:58:31.045064] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"aegildsksa0i5184igdk12pdg3"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
6853:[2026-04-30 20:58:31.174884] Admidio.INFO: Set Cookie! {"name":"ADMIDIO_admidio_adm_SESSION_ID","value":"9vsc7c5qv9cr4cavugitg6i2l3","expire":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":533,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"setCookie"}
6878:[2026-04-30 20:58:31.184031] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"9vsc7c5qv9cr4cavugitg6i2l3"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
7010:[2026-04-30 20:58:40.393679] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"nr7mssfl6eupo9d2pboea7hmb2"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
7154:[2026-04-30 20:58:40.438503] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"nr7mssfl6eupo9d2pboea7hmb2"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
7185:[2026-04-30 20:58:40.564244] Admidio.INFO: Set Cookie! {"name":"ADMIDIO_admidio_adm_SESSION_ID","value":"sts5aqfsvqghtl6bfq79a3ap2t","expire":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":533,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"setCookie"}
7210:[2026-04-30 20:58:40.571305] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"sts5aqfsvqghtl6bfq79a3ap2t"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
7342:[2026-04-30 20:58:40.611506] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"sts5aqfsvqghtl6bfq79a3ap2t"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
7414:[2026-04-30 21:01:44.898211] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"dcgm8ebt3hkhmvvk9n860r6i5n"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
7558:[2026-04-30 21:01:44.940724] Admidio.INFO: Session Started! {"name":"ADMIDIO_admidio_adm_SESSION_ID","limit":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax","sessionId":"dcgm8ebt3hkhmvvk9n860r6i5n"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":617,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"start"}
7591:[2026-04-30 21:01:45.066694] Admidio.INFO: Set Cookie! {"name":"ADMIDIO_admidio_adm_AUTO_LOGIN_ID","value":"2:nO2BhCdRgFUMKT46e2EzS79Inf4oWiLWzLnX9Ko5","expire":1809118905,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":533,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"setCookie"}
7596:[2026-04-30 21:01:45.068352] Admidio.INFO: Set Cookie! {"name":"ADMIDIO_admidio_adm_SESSION_ID","value":"iga3ujr67cti6s7btnuhecte67","expire":0,"path":"/","domain":false,"secure":false,"httpOnly":true,"sameSite":"lax"} {"file":"/opt/app-root/src/src/Session/Entity/Session.php","line":533,"class":"Admidio\\Session\\Entity\\Session","callType":"::","function":"setCookie"}

Impact

Any actor with log access can replay or abuse current session IDs and auto-login cookies, leading to session hijacking or long-lived account access depending on deployment and cookie lifetime.

Remediation And Suggestions

Never log raw session identifiers or cookie values. Replace them with fixed labels or redact most of the value before logging.

$gLogger->info('Set Cookie!', [
'name' => $name,
'value' => '[redacted]',
'expire' => $expire,
'path' => $path,
'domain' => $domain,
'secure' => $secure,
'httpOnly' => $httpOnly,
'sameSite' => 'lax',
]);

$gLogger->info('Session Started!', [
'name' => $sessionName,
'limit' => $limit,
'path' => $path,
'domain' => $domain,
'secure' => $secure,
'httpOnly' => $httpOnly,
'sameSite' => 'lax',
'sessionId' => '[redacted]',
]);