REDHAT-BUG-2490669: Buffer Overflow

Q: What conditions are required to trigger this issue?

The overflow occurs when scaffold backing-array reallocation is mishandled while data structures are shared across parsers. Exploitation therefore requires XML parsing activity involving cross-parser data-structure sharing.

Q: Which libexpat versions are affected?

libexpat versions before 2.8.2 are affected. Systems using an earlier version should review the referenced Red Hat advisories for applicable updates.

Q: What is the impact of successful exploitation?

Successful triggering causes a heap-based buffer overflow in doProlog in xmlparse.c. The provided information does not specify further impact such as code execution, denial of service, or information disclosure.

Published Jun 19, 2026

Updated

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.

Affected Software

1 affected component

Expat libexpat<2.8.2

Event History

Jun 19, 2026

Data Sourced

via Red Hat·05:01 AM

DescriptionSeverityAffected Software

Frequently Asked Questions

What conditions are required to trigger this issue?

The overflow occurs when scaffold backing-array reallocation is mishandled while data structures are shared across parsers. Exploitation therefore requires XML parsing activity involving cross-parser data-structure sharing.

Which libexpat versions are affected?

libexpat versions before 2.8.2 are affected. Systems using an earlier version should review the referenced Red Hat advisories for applicable updates.

What is the impact of successful exploitation?

Successful triggering causes a heap-based buffer overflow in doProlog in xmlparse.c. The provided information does not specify further impact such as code execution, denial of service, or information disclosure.

REDHAT-BUG-2490669: Buffer Overflow

Affected Software

Event History

Frequently Asked Questions

What conditions are required to trigger this issue?

Which libexpat versions are affected?

What is the impact of successful exploitation?

Company

Resources

Contact

Frequently Asked Questions

What conditions are required to trigger this issue?

Which libexpat versions are affected?

What is the impact of successful exploitation?