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CVE-2026-102509

Apache PLC4X, Apache PLC4X: Pre-authentication resource exhaustion in the OPC UA driver and the Java SPI parser

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 1.0.0
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: yes
  • Technical impact: partial

Summary

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. In 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 impersonate it. The individual defects are: • 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). • 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). • The OPC UA driver accumulates message chunks without enforcing the negotiated maximum chunk count and message size (0.12.0 through 0.13.1). • The OPC UA driver pre-allocates collections using element counts received from the server (0.10.0 through 0.13.1). • 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 . This issue affects Apache PLC4X: from 0.10.0 before 1.0.0. Users are recommended to upgrade to version 1.0.0, which fixes the issue.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: yes · Technical impact: partial

  3. Record last updated

Affected versions

  • org.apache.plc4x:plc4j-spi

    From 0.10.0 · fixed in 1.0.0

  • org.apache.plc4x:plc4j-driver-opcua

    From 0.10.0 · fixed in 1.0.0

References 1

lists.apache.org