An issue was discovered in Squid through 4.7. When Squid is parsing ESI, it keeps the ESI elements in ESIContext. ESIContext contains a buffer for holding a stack of ESIElements. When a new ESIElement is parsed, it is added via addStackElement. addStackElement has a check for the number of elements in this buffer, but it's off by 1, leading to a Heap Overflow of 1 element. The overflow is within the same structure so it can't affect adjacent memory blocks, and thus just leads to a crash while processing.
Image SLES15-SP1-Manager-4-0-Azure-BYOS-Proxy Image SLES15-SP1-Manager-4-0-EC2-HVM-BYOS-Proxy Image SLES15-SP1-Manager-4-0-GCE-BYOS-Proxy Image SLES15-SP2-Manager-4-1-Proxy-BYOS-Azure Image SLES15-SP2-Manager-4-1-Proxy-BYOS-EC2-HVM Image SLES15-SP2-Manager-4-1-Proxy-BYOS-GCE Image SLES15-SP3-Manager-4-2-Proxy-BYOS-Azure Image SLES15-SP3-Manager-4-2-Proxy-BYOS-EC2-HVM Image SLES15-SP3-Manager-4-2-Proxy-BYOS-GCE openSUSE Leap 15.1 SUSE CaaS Platform 4.0 SUSE Linux Enterprise High Performance Computing 15 SP1 SUSE Linux Enterprise High Performance Computing 15 SP2 SUSE Linux Enterprise High Performance Computing 15 SP3 SUSE Linux Enterprise High Performance Computing 15 SP4 SUSE Linux Enterprise High Performance Computing 15-ESPOS SUSE Linux Enterprise High Performance Computing 15-LTSS SUSE Linux Enterprise Module for Server Applications 15 SP1 SUSE Linux Enterprise Module for Server Applications 15 SP2 SUSE Linux Enterprise Module for Server Applications 15 SP3 SUSE Linux Enterprise Module for Server Applications 15 SP4 SUSE Linux Enterprise Point of Sale 11 SP3 SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT SUSE Linux Enterprise Server 11 SP1-TERADATA SUSE Linux Enterprise Server 11 SP3-TERADATA SUSE Linux Enterprise Server 11 SP4-LTSS SUSE Linux Enterprise Server 12 SP2-BCL SUSE Linux Enterprise Server 12 SP2-ESPOS SUSE Linux Enterprise Server 12 SP2-LTSS SUSE Linux Enterprise Server 12 SP3-BCL SUSE Linux Enterprise Server 12 SP3-ESPOS SUSE Linux Enterprise Server 12 SP3-LTSS SUSE Linux Enterprise Server 12 SP3-TERADATA SUSE Linux Enterprise Server 12 SP4 SUSE Linux Enterprise Server 12 SP5 SUSE Linux Enterprise Server 15 SP1 SUSE Linux Enterprise Server 15 SP2 SUSE Linux Enterprise Server 15 SP3 SUSE Linux Enterprise Server 15 SP4 SUSE Linux Enterprise Server 15-LTSS SUSE Linux Enterprise Server for SAP Applications 11 SP1-TERADATA SUSE Linux Enterprise Server for SAP Applications 11 SP3-TERADATA SUSE Linux Enterprise Server for SAP Applications 11 SP4-LTSS SUSE Linux Enterprise Server for SAP Applications 12 SP2 SUSE Linux Enterprise Server for SAP Applications 12 SP2-BCL SUSE Linux Enterprise Server for SAP Applications 12 SP2-ESPOS SUSE Linux Enterprise Server for SAP Applications 12 SP2-LTSS SUSE Linux Enterprise Server for SAP Applications 12 SP3 SUSE Linux Enterprise Server for SAP Applications 12 SP3-BCL SUSE Linux Enterprise Server for SAP Applications 12 SP3-ESPOS SUSE Linux Enterprise Server for SAP Applications 12 SP3-LTSS SUSE Linux Enterprise Server for SAP Applications 12 SP3-TERADATA SUSE Linux Enterprise Server for SAP Applications 12 SP4 SUSE Linux Enterprise Server for SAP Applications 12 SP5 SUSE Linux Enterprise Server for SAP Applications 15 SUSE Linux Enterprise Server for SAP Applications 15 SP1 SUSE Linux Enterprise Server for SAP Applications 15 SP2 SUSE Linux Enterprise Server for SAP Applications 15 SP3 SUSE Linux Enterprise Server for SAP Applications 15 SP4 SUSE Linux Enterprise Storage 6 SUSE Linux Enterprise Storage 7 SUSE Linux Enterprise Storage 7.1 SUSE Manager Proxy 4.0 SUSE Manager Proxy 4.1 SUSE Manager Proxy 4.2 SUSE Manager Proxy 4.3 SUSE Manager Retail Branch Server 4.0 SUSE Manager Retail Branch Server 4.1 SUSE Manager Retail Branch Server 4.2 SUSE Manager Retail Branch Server 4.3 SUSE Manager Server 4.0 SUSE Manager Server 4.1 SUSE Manager Server 4.2 SUSE Manager Server 4.3 SUSE OpenStack Cloud 7 SUSE OpenStack Cloud 8 SUSE OpenStack Cloud Crowbar 8