{"id":"CVE-2026-102509","published":"2026-09-30T09:17:14.100","lastModified":"2026-09-30T16:14:10.347","description":"Memory Allocation with Excessive Size Value, Allocation of Resources Without Limits, and Uncontrolled Recursion in the Java implementation of Apache PLC4X (PLC4J) allow a malicious or impersonated device to exhaust the memory or stack of the client application, causing a denial of service.\n\nIn the OPC UA driver these defects are reachable before authentication: the offending data is parsed while the secure channel and session are being established, before the server's identity has been bound to it. Configuring a trusted server therefore does not prevent exploitation by an attacker who can \nimpersonate it.\n\nThe individual defects are:\n- Length-prefixed byte strings are allocated at the size claimed on the wire before the length is checked against the data actually received (0.10.0 through 0.13.1).\n- Array fields in generated protocol parsers pre-allocate a list with the element count claimed on the wire, allowing a single count field to trigger a multi-gigabyte allocation. This parser is shared by all PLC4J drivers; the OPC UA driver is the verified pre-authentication path (0.10.0 through 0.13.1).\n- The OPC UA driver accumulates message chunks without enforcing the negotiated maximum chunk count and message size (0.12.0 through 0.13.1).\n- The OPC UA driver pre-allocates collections using element counts received from the server (0.10.0 through 0.13.1).\n- Recursive protocol types are parsed without a nesting-depth limit. The same defect in the Go implementation is covered by  CVE-2026-102510 https://cveprocess.apache.org/cve5/CVE-2026-102510 .\n\nThis issue affects Apache PLC4X: from 0.10.0 before 1.0.0.\n\nUsers are recommended to upgrade to version 1.0.0, which fixes the issue.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":["CWE-674","CWE-770","CWE-789"],"vendors":[],"products":[],"references":[{"url":"https://lists.apache.org/thread.html/qngc85qhnlj7kpk3z58z0xlxhz2tn6gp","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}