{"id":"CVE-2026-102509","aliases":["EUVD-2026-89678","GHSA-c34c-r8hh-6grp"],"status":"published","title":"Apache PLC4X, Apache PLC4X: Pre-authentication resource exhaustion in the OPC UA driver and the Java SPI parser","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.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00438,"percentile":0.38538,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-674","CWE-770","CWE-789"],"published":"2026-09-30T08:00:27Z","modified":"2026-09-30T16:14:10Z","products":[{"vendor":"apache software foundation","product":"apache plc4x"}],"references":[{"url":"https://lists.apache.org/thread.html/qngc85qhnlj7kpk3z58z0xlxhz2tn6gp","tags":["vendor-advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102509"},{"url":"https://github.com/advisories/GHSA-c34c-r8hh-6grp"}],"sources":{"cve":[{"id":"CVE-2026-102509","title":"Apache PLC4X, Apache PLC4X: Pre-authentication resource exhaustion in the OPC UA driver and the Java SPI parser","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.","status":"published","published":"2026-09-30T08:00:27.709Z","modified":"2026-09-30T14:40:06.881Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"}],"cwes":["CWE-789","CWE-770","CWE-674"],"updated_at":"2026-11-02T13:38:54.394896Z"}],"euvd":[{"id":"EUVD-2026-89678","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.","status":"published","published":"2026-09-30T08:00:27Z","modified":"2026-09-30T14:40:06Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T17:27:49.499669Z"}],"ghsa":[{"id":"GHSA-c34c-r8hh-6grp","title":"Memory Allocation with Excessive Size Value, Allocation of Resources Without Limits, and...","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.","status":"published","published":"2026-09-30T09:31:11Z","modified":"2026-09-30T09:31:21Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"}],"cwes":["CWE-674"],"updated_at":"2026-11-02T15:12:35.884172Z"}],"nvd":[{"id":"CVE-2026-102509","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.","status":"published","published":"2026-09-30T09:17:14.1Z","modified":"2026-09-30T16:14:10.347Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"}],"cwes":["CWE-674","CWE-770","CWE-789"],"updated_at":"2026-11-02T14:12:52.759595Z"}]}}