CVE-2021-3850: Authentication Bypass in ADOdb/ADOdb

Impact

An attacker can inject values into a PostgreSQL connection string by providing a parameter surrounded by single quotes.

Depending on how the library is used in the client software, this may allow an attacker to bypass the login process, gain access to the server's IP address, etc.

Patches

The vulnerability is fixed in ADOdb versions 5.20.21 (952de6c4273d9b1e91c2b838044f8c2111150c29) and 5.21.4 or later (b4d5ce70034c5aac3a1d51d317d93c037a0938d2).

The simplest patch is to delete line 29 in drivers/adodb-postgres64.inc.php:

php diff --git a/drivers/adodb-postgres64.inc.php b/drivers/adodb-postgres64.inc.php index d04b7f67..729d7141 100644 --- a/drivers/adodb-postgres64.inc.php +++ b/drivers/adodb-postgres64.inc.php @@ -26,7 +26,6 @@ function adodbaddslashes($s) { $len = strlen($s); if ($len == 0) return "''"; - if (strncmp($s,"'",1) === 0 && substr($s,$len-1) == "'") return $s; // already quoted return "'".addslashes($s)."'"; }

Workarounds

Ensure the parameters passed to ADOConnection::connect() or related functions (nConnect(), pConnect()) are not surrounded by single quotes.

Credits

Thanks to Emmet Leahy (@meme-lord) of Sorcery Ltd for reporting this vulnerability, and to the huntr team for their support.

References

- Original issue report https://huntr.dev/bounties/bdf5f216-4499-4225-a737-b28bc6f5801c/ - ADOdb reference issue #793

For more information

If you have any questions or comments about this advisory: Add a note in issue #793 Contact the maintainers on Gitter