Vulnerability identifier: #VU26104
Vulnerability risk: Medium
Exploitation vector: Network
Exploit availability: No
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference in tls_verify_crl() function in ProFTPD while processing data, returned by the OpenSSL sk_X509_REVOKED_value() function when encountering an empty CRL installed by a system administrator. A remote attacker can trigger the NULL pointer dereference error when validating the certificate of a client connecting to the server in a TLS client/server mutual-authentication setup.
Successful exploitation of the vulnerability will result in a denial of service condition.
Install updates from vendor's website.
Vulnerable software versions
ProFTPD: 1.3.0 - 1.3.6b
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.