{"cve":"CVE-2026-102509","nvd":{"published":"2026-09-30T09:17:14.100","modified":"2026-09-30T16:14:10.347","status":"Awaiting Analysis","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.","cvss_v4":{"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","score":8.7},"cvss_v3":null,"cwes":["CWE-674","CWE-770","CWE-789"],"references":["https://lists.apache.org/thread.html/qngc85qhnlj7kpk3z58z0xlxhz2tn6gp"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:48.555445741+00:00"},"epss":{"cve":"CVE-2026-102509","score":0.00438,"percentile":0.37779,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}