CVE-2026-56406: CWE-190 Integer Overflow or Wraparound in libexpat project libexpat
libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.
AI Analysis
Technical Summary
CVE-2026-56406 is an integer overflow vulnerability in the libexpat XML parsing library prior to version 2.8.2. The issue arises because XML_ParseBuffer lacks an integer overflow check that is implemented in XML_Parse, potentially allowing an attacker to cause memory corruption or other unintended behavior during XML parsing. This vulnerability affects local attack vectors with high attack complexity and no privileges or user interaction required. The impact includes high confidentiality and integrity loss, with low impact on availability.
Potential Impact
The vulnerability can lead to high impact on confidentiality and integrity, potentially allowing an attacker to manipulate or disclose sensitive data processed by libexpat. The availability impact is low. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch information is provided in the available data. Users should monitor libexpat project advisories for updates and apply any forthcoming patches promptly.
CVE-2026-56406: CWE-190 Integer Overflow or Wraparound in libexpat project libexpat
Description
libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.
CVSS v3.1
Score 6.9medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-56406 is an integer overflow vulnerability in the libexpat XML parsing library prior to version 2.8.2. The issue arises because XML_ParseBuffer lacks an integer overflow check that is implemented in XML_Parse, potentially allowing an attacker to cause memory corruption or other unintended behavior during XML parsing. This vulnerability affects local attack vectors with high attack complexity and no privileges or user interaction required. The impact includes high confidentiality and integrity loss, with low impact on availability.
Potential Impact
The vulnerability can lead to high impact on confidentiality and integrity, potentially allowing an attacker to manipulate or disclose sensitive data processed by libexpat. The availability impact is low. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch information is provided in the available data. Users should monitor libexpat project advisories for updates and apply any forthcoming patches promptly.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-06-21T15:48:21.578Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a380caeeed863c81e0981aa
Added to database: 06/21/2026, 16:09:18 UTC
Last enriched: 06/28/2026, 21:55:08 UTC
Last updated: 08/05/2026, 00:41:15 UTC
Views: 98
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