collectd: double free in csnmp_read_table function in snmp.c

The csnmp_read_table function in snmp.c in the SNMP plugin in collectd before 5.6.3 is susceptible to a double free in a certain error case, which could lead to a crash (or potentially have other impact).

collectd: Infinite loop due to incorrect interaction of parse_packet() and parse_part_sign_sha256() functions

Incorrect interaction of the parse_packet() and parse_part_sign_sha256() functions in network.c in collectd 5.7.1 and earlier allows remote attackers to cause a denial of service (infinite loop) of a collectd instance (configured with "SecurityLevel None" and with empty "AuthFile" options) via a crafted UDP packet.

collectd: heap overflow in the network plugin

Heap-based buffer overflow in the parse_packet function in network.c in collectd before 5.4.3 and 5.x before 5.5.2 allows remote attackers to cause a denial of service (daemon crash) or possibly execute arbitrary code via a crafted network packet.

The cu_rrd_create_file function (src/utils_rrdcreate.c) in collectd 4.x before 4.9.4 and before 4.10.2 allow remote attackers to cause a denial of service (assertion failure) via a packet with a timestamp whose value is 10 or less, as demonstrated by creating RRD files using the (1) RRDtool and (2) RRDCacheD plugins.

The Gentoo app-admin/collectd package before 5.7.2-r1 sets the ownership of PID file directory to the collectd account, which might allow local users to kill arbitrary processes by leveraging access to this account for PID file modification before a root script sends a SIGKILL (when the service is stopped).