Multiple integer overflows in pktlength.c in Chrony before 1.29 allow remote attackers to cause a denial of service (crash) via a crafted (1) REQ_SUBNETS_ACCESSED or (2) REQ_CLIENT_ACCESSES command request to the PKL_CommandLength function or crafted (3) RPY_SUBNETS_ACCESSED, (4) RPY_CLIENT_ACCESSES, (5) RPY_CLIENT_ACCESSES_BY_INDEX, or (6) RPY_MANUAL_LIST command reply to the PKL_ReplyLength function, which triggers an out-of-bounds read or buffer overflow. NOTE: versions 1.27 and 1.28 do not require authentication to exploit.

cmdmon.c in Chrony before 1.29 allows remote attackers to obtain potentially sensitive information from stack memory via vectors related to (1) an invalid subnet in a RPY_SUBNETS_ACCESSED command to the handle_subnets_accessed function or (2) a RPY_CLIENT_ACCESSES command to the handle_client_accesses function when client logging is disabled, which causes uninitialized data to be included in a reply.