CVE-2026-56409: CWE-190 Integer Overflow or Wraparound in libexpat project libexpat
An integer overflow vulnerability exists in the xmlwf tool of the libexpat project before version 2.8.2. This overflow occurs when specifying an output directory with the -d option, potentially causing memory corruption or other impacts related to integer wraparound.
AI Analysis
Technical Summary
CVE-2026-56409 is an integer overflow vulnerability (CWE-190) in the xmlwf utility of the libexpat project. The issue arises when the -d outputDir option is used, leading to an integer overflow in the calculation of the output filename size. This vulnerability affects versions of libexpat prior to 2.8.2. The CVSS 3.1 base score is 6.5, indicating a medium severity with high impact on confidentiality and integrity, and low impact on availability. The attack vector is local with high attack complexity and requires user interaction.
Potential Impact
Successful exploitation could lead to high confidentiality and integrity impacts due to the integer overflow potentially allowing memory corruption or unexpected behavior in file handling. Availability impact is low. The vulnerability requires local access and user interaction, limiting the attack surface.
Mitigation Recommendations
No official patch or remediation level is currently stated. Since the vulnerability affects versions before 2.8.2, upgrading to libexpat version 2.8.2 or later (once available) is recommended. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
CVE-2026-56409: CWE-190 Integer Overflow or Wraparound in libexpat project libexpat
Description
An integer overflow vulnerability exists in the xmlwf tool of the libexpat project before version 2.8.2. This overflow occurs when specifying an output directory with the -d option, potentially causing memory corruption or other impacts related to integer wraparound.
CVSS v3.1
Score 6.5medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-56409 is an integer overflow vulnerability (CWE-190) in the xmlwf utility of the libexpat project. The issue arises when the -d outputDir option is used, leading to an integer overflow in the calculation of the output filename size. This vulnerability affects versions of libexpat prior to 2.8.2. The CVSS 3.1 base score is 6.5, indicating a medium severity with high impact on confidentiality and integrity, and low impact on availability. The attack vector is local with high attack complexity and requires user interaction.
Potential Impact
Successful exploitation could lead to high confidentiality and integrity impacts due to the integer overflow potentially allowing memory corruption or unexpected behavior in file handling. Availability impact is low. The vulnerability requires local access and user interaction, limiting the attack surface.
Mitigation Recommendations
No official patch or remediation level is currently stated. Since the vulnerability affects versions before 2.8.2, upgrading to libexpat version 2.8.2 or later (once available) is recommended. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-06-21T15:52:59.313Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a380caeeed863c81e0981b3
Added to database: 06/21/2026, 16:09:18 UTC
Last enriched: 06/21/2026, 16:24:09 UTC
Last updated: 06/22/2026, 00:53:04 UTC
Views: 12
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