Red Hat Security Advisory: expat security update
Two security vulnerabilities have been identified in the Expat C library used for XML parsing. The first is a denial of service vulnerability caused by quadratic complexity in attribute processing (CVE-2026-66046). The second is an XML injection vulnerability via malformed UTF-16 input (CVE-2026-93990). Red Hat has issued an important security advisory and released updates for Red Hat Enterprise Linux 8 to address these issues. Users of affected Red Hat Enterprise Linux 8 variants are advised to apply the provided updates to mitigate these vulnerabilities.
AI Analysis
Technical Summary
Expat, a C library for parsing XML documents, has two security issues: CVE-2026-66046, a denial of service vulnerability due to quadratic complexity in attribute processing, and CVE-2026-93990, an XML injection vulnerability caused by malformed UTF-16 input. Red Hat has released security updates for Red Hat Enterprise Linux 8 across multiple architectures and extended life cycle versions to fix these vulnerabilities. The advisory rates the impact as important and provides updated packages to remediate the issues.
Potential Impact
The denial of service vulnerability (CVE-2026-66046) could allow an attacker to cause resource exhaustion by exploiting quadratic complexity in attribute processing. The XML injection vulnerability (CVE-2026-93990) could allow injection of malicious XML content via malformed UTF-16 input, potentially leading to unexpected behavior in applications using the library. These vulnerabilities affect Red Hat Enterprise Linux 8 and its extended life cycle variants on multiple architectures.
Mitigation Recommendations
Red Hat has released updated expat packages for Red Hat Enterprise Linux 8 and its extended life cycle versions. Users should apply these official updates as described in the Red Hat advisory (https://access.redhat.com/articles/11258) to remediate the vulnerabilities. No additional mitigation steps are indicated beyond applying the provided patches.
Red Hat Security Advisory: expat security update
Description
Two security vulnerabilities have been identified in the Expat C library used for XML parsing. The first is a denial of service vulnerability caused by quadratic complexity in attribute processing (CVE-2026-66046). The second is an XML injection vulnerability via malformed UTF-16 input (CVE-2026-93990). Red Hat has issued an important security advisory and released updates for Red Hat Enterprise Linux 8 to address these issues. Users of affected Red Hat Enterprise Linux 8 variants are advised to apply the provided updates to mitigate these vulnerabilities.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Expat, a C library for parsing XML documents, has two security issues: CVE-2026-66046, a denial of service vulnerability due to quadratic complexity in attribute processing, and CVE-2026-93990, an XML injection vulnerability caused by malformed UTF-16 input. Red Hat has released security updates for Red Hat Enterprise Linux 8 across multiple architectures and extended life cycle versions to fix these vulnerabilities. The advisory rates the impact as important and provides updated packages to remediate the issues.
Potential Impact
The denial of service vulnerability (CVE-2026-66046) could allow an attacker to cause resource exhaustion by exploiting quadratic complexity in attribute processing. The XML injection vulnerability (CVE-2026-93990) could allow injection of malicious XML content via malformed UTF-16 input, potentially leading to unexpected behavior in applications using the library. These vulnerabilities affect Red Hat Enterprise Linux 8 and its extended life cycle variants on multiple architectures.
Mitigation Recommendations
Red Hat has released updated expat packages for Red Hat Enterprise Linux 8 and its extended life cycle versions. Users should apply these official updates as described in the Red Hat advisory (https://access.redhat.com/articles/11258) to remediate the vulnerabilities. No additional mitigation steps are indicated beyond applying the provided patches.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:72448
- Cve Count
- 2
- Additional Cves
- ["CVE-2026-93990"]
- State
- PUBLISHED
Threat ID: 6abb4186f7a7c54106cc2f6e
Added to database: 09/29/2026, 04:41:42 UTC
Last enriched: 09/29/2026, 04:46:19 UTC
Last updated: 09/29/2026, 18:13:11 UTC
Views: 3
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