CVE-2026-56132: CWE-821 Incorrect Synchronization in libexpat project libexpat
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.
AI Analysis
Technical Summary
CVE-2026-56132 is a heap-based buffer overflow in the libexpat XML parsing library before version 2.8.2. The flaw arises from improper synchronization and mishandling of scaffold backing array reallocation in the doProlog function when data structures are shared across multiple parsers. This can result in memory corruption, potentially allowing an attacker to compromise confidentiality and integrity of the application using libexpat.
Potential Impact
The vulnerability allows for high impact on confidentiality and integrity due to heap-based buffer overflow, which could lead to unauthorized data disclosure or modification. The availability impact is low. There are no known exploits in the wild as of the published date.
Mitigation Recommendations
A fix is available in libexpat version 2.8.2 and later. Users should upgrade to version 2.8.2 or newer to remediate this vulnerability. Patch status is not explicitly confirmed beyond the version indication; therefore, check the vendor advisory for the latest remediation guidance.
CVE-2026-56132: CWE-821 Incorrect Synchronization in libexpat project libexpat
Description
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.
CVSS v3.1
Score 6.9medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-56132 is a heap-based buffer overflow in the libexpat XML parsing library before version 2.8.2. The flaw arises from improper synchronization and mishandling of scaffold backing array reallocation in the doProlog function when data structures are shared across multiple parsers. This can result in memory corruption, potentially allowing an attacker to compromise confidentiality and integrity of the application using libexpat.
Potential Impact
The vulnerability allows for high impact on confidentiality and integrity due to heap-based buffer overflow, which could lead to unauthorized data disclosure or modification. The availability impact is low. There are no known exploits in the wild as of the published date.
Mitigation Recommendations
A fix is available in libexpat version 2.8.2 and later. Users should upgrade to version 2.8.2 or newer to remediate this vulnerability. Patch status is not explicitly confirmed beyond the version indication; therefore, check the vendor advisory for the latest remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-06-19T03:00:42.577Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a34c723f198dc38c1785b28
Added to database: 06/19/2026, 04:35:47 UTC
Last enriched: 07/03/2026, 23:07:46 UTC
Last updated: 08/01/2026, 07:18:01 UTC
Views: 120
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