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CVE-2026-6732 Red Hat CVE debrief

CVE-2026-6732 is a denial of service (DoS) vulnerability in libxml2, a widely used XML parsing library. The vulnerability occurs when the library processes a specially crafted XML Schema Definition (XSD) validated document that includes an internal entity reference. An attacker could exploit this by providing a malicious document, leading to a type confusion error that causes the application to crash. This results in a denial of service (DoS), making the affected system or application unavailable. The Common Vulnerability Scoring System (CVSS) score for this vulnerability is 6.5, indicating a medium severity level. The CVSS vector is CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Vendor
Red Hat
Product
Red Hat Hardened Images
CVSS
MEDIUM 6.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-23
Original CVE updated
2026-08-31
Advisory published
2026-04-23
Advisory updated
2026-08-31

Who should care

Organizations and individuals who use libxml2 in their applications or systems should be aware of this vulnerability. This includes developers, system administrators, and security professionals responsible for maintaining and securing software that relies on libxml2 for XML parsing. Red Hat products, including Red Hat Enterprise Linux, are affected by this vulnerability.

Technical summary

The vulnerability is caused by a type confusion error in libxml2 when processing a specially crafted XML Schema Definition (XSD) validated document with an internal entity reference. This can lead to a denial of service (DoS) condition, causing the application to crash. The vulnerability has a CVSS score of 6.5 and a CVSS vector of CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. The affected products include libxml2 versions prior to 2.15.3, Red Hat Enterprise Linux, and IBM AIX.

Defensive priority

Apply patches or updates to libxml2 to fix the vulnerability. Review and update affected Red Hat products, such as Red Hat Enterprise Linux, and IBM AIX systems.

Recommended defensive actions

  • Apply patches or updates to libxml2 to fix the vulnerability.
  • Review and update affected Red Hat products, such as Red Hat Enterprise Linux.
  • Review and update IBM AIX systems.
  • Monitor systems and applications for signs of exploitation.
  • Implement compensating controls, such as input validation and sanitization.

Evidence notes

The CVE-2026-6732 vulnerability was publicly disclosed on April 23, 2026, and the CVE record was last modified on June 30, 2026. The vulnerability affects libxml2, a widely used XML parsing library. Red Hat products, including Red Hat Enterprise Linux, are affected by this vulnerability. IBM AIX systems are also affected.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-6732 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-6732

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-6732 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-6732

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.