CVE-2026-56406
MEDIUMCVSS 6.9/10EPSS 0.10%
Last modified
CVE-2026-56406 is a medium-severity vulnerability rated 6.9/10 on the CVSS scale. libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.. EPSS estimates a 0.10% chance of exploitation in the next 30 days.
Description
libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.
Metrics
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Libexpat Project | Libexpat | < 2.8.2 |
References
- https://github.com/libexpat/libexpat/pull/1255Patch, Issue Tracking
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-56406?
libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.
How severe is CVE-2026-56406?
CVE-2026-56406 has a CVSS score of 6.9/10 (MEDIUM severity). The EPSS model estimates a 0.10% probability of exploitation in the next 30 days.
How do I fix CVE-2026-56406?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
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Are you affected by CVE-2026-56406?
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Scan your code nowSource: NVD / NIST