CVE-2026-56403: CWE-190 Integer Overflow or Wraparound in libexpat project libexpat
CVE-2026-56403 is an integer overflow vulnerability in the libexpat library affecting versions before 2.8.2. The flaw exists in the storeAtts function and could lead to high confidentiality and integrity impact, with low availability impact. The vulnerability has a CVSS score of 6.9, indicating medium severity. No official patch or remediation information is currently available.
AI Analysis
Technical Summary
This vulnerability in libexpat before version 2.8.2 involves an integer overflow or wraparound in the storeAtts function. The issue could potentially allow an attacker with local access and high attack complexity to cause a compromise of confidentiality and integrity with limited impact on availability. The CVSS vector indicates no privileges required and no user interaction, but the attack complexity is high and the attack vector is local.
Potential Impact
Successful exploitation could lead to a high impact on confidentiality and integrity of the affected system, with a low impact on availability. The vulnerability could allow an attacker to manipulate memory or data structures due to the integer overflow, potentially leading to unauthorized information disclosure or data corruption.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround has been documented at this time.
CVE-2026-56403: CWE-190 Integer Overflow or Wraparound in libexpat project libexpat
Description
CVE-2026-56403 is an integer overflow vulnerability in the libexpat library affecting versions before 2.8.2. The flaw exists in the storeAtts function and could lead to high confidentiality and integrity impact, with low availability impact. The vulnerability has a CVSS score of 6.9, indicating medium severity. No official patch or remediation information is currently available.
CVSS v3.1
Score 6.9medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in libexpat before version 2.8.2 involves an integer overflow or wraparound in the storeAtts function. The issue could potentially allow an attacker with local access and high attack complexity to cause a compromise of confidentiality and integrity with limited impact on availability. The CVSS vector indicates no privileges required and no user interaction, but the attack complexity is high and the attack vector is local.
Potential Impact
Successful exploitation could lead to a high impact on confidentiality and integrity of the affected system, with a low impact on availability. The vulnerability could allow an attacker to manipulate memory or data structures due to the integer overflow, potentially leading to unauthorized information disclosure or data corruption.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround has been documented at this time.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-06-21T15:43:55.436Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a380caeeed863c81e0981a1
Added to database: 06/21/2026, 16:09:18 UTC
Last enriched: 06/21/2026, 16:24:34 UTC
Last updated: 06/22/2026, 02:38:44 UTC
Views: 9
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