In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.

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Incorrect Synchronization

Overview Affected versions of this package are vulnerable to Incorrect Synchronization in the doProlog function in xmlparse.c due to improper handling of scaffold backing array reallocation when data structures are shared across multiple parsers. An attacker can achieve arbitrary code execution o...

CVE-2026-56132

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers...