FreeBSD : zeek -- potential denial of service issues (4ae135f7-85cd-4c32-ad94-358271b31f7f)

high Nessus Plugin ID 134585


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The remote FreeBSD host is missing a security-related update.


Jon Siwek of Corelight reports :

This release addresses the following security issues :

- Potential Denial of Service due to memory leak in DNS TSIG message parsing.

- Potential Denial of Service due to memory leak (or assertion when compiling with assertions enabled) when receiving a second SSH KEX message after a first.

- Potential Denial of Service due to buffer read overflow and/or memory leaks in Kerberos analyzer. The buffer read overflow could occur when the Kerberos message indicates it contains an IPv6 address, but does not send enough data to parse out a full IPv6 address. A memory leak could occur when processing KRB_KDC_REQ KRB_KDC_REP messages for message types that do not match a known/expected type.

- Potential Denial of Service when sending many zero-length SSL/TLS certificate data. Such messages underwent the full Zeek file analysis treatment which is expensive (and meaninguless here) compared to how cheaply one can 'create' or otherwise indicate many zero-length contained in an SSL message.

- Potential Denial of Service due to buffer read overflow in SMB transaction data string handling. The length of strings being parsed from SMB messages was trusted to be whatever the message claimed instead of the actual length of data found in the message.

- Potential Denial of Service due to NULL pointer dereference in FTP ADAT Base64 decoding.

- Potential Denial of Service due buffer read overflow in FTP analyzer word/whitespace handling. This typically won't be a problem in most default deployments of Zeek since the FTP analyzer receives data from a ContentLine (NVT) support analyzer which first null-terminates the buffer used for further FTP parsing.


Update the affected package.

See Also

Plugin Details

Severity: High

ID: 134585

File Name: freebsd_pkg_4ae135f785cd4c32ad94358271b31f7f.nasl

Version: 1.1

Type: local

Published: 3/16/2020

Updated: 3/16/2020

Dependencies: ssh_get_info.nasl

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:zeek, cpe:/o:freebsd:freebsd

Required KB Items: Host/local_checks_enabled, Host/FreeBSD/release, Host/FreeBSD/pkg_info

Patch Publication Date: 3/15/2020

Vulnerability Publication Date: 2/25/2020