#VU26104 NULL pointer dereference in ProFTPD - CVE-2019-19269
Published: March 17, 2020 / Updated: September 7, 2020
Vulnerability identifier: #VU26104
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2019-19269
CWE-ID: CWE-476
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
ProFTPD
ProFTPD
Software vendor:
ProFTPD
ProFTPD
Description
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.
Remediation
Install updates from vendor's website.
External links
- http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00009.html
- https://github.com/proftpd/proftpd/issues/861
- https://lists.debian.org/debian-lts-announce/2019/11/msg00039.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OGBBCPLJSDPFG5EI5P5G7P4KEX7YSD5G/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QR65XUHPCRU3NXTSFVF2J4GWRIHC7AHW/