CVE-2026-66046 Expat Denial of Service via storeAtts() Quadratic Complexity

Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an ON^2 linear scan of elementType-defaultAtts to determine CDATA status. ...

JLSEC-2026-1226

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers...

Important: expat

Issue Overview: In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers. CVE-2026-56132 Affected Packages: expat Note: This advisory is applicable to...

Important: expat

Issue Overview: In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers. CVE-2026-56132 Affected Packages: expat Issue Correction: Run dnf update expat...

SUSE CVE-2026-56132

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers...

ALPINE-CVE-2026-56132

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers...

CVE-2026-56132

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers...

CVE-2026-56132

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers...

CVE-2026-56132

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers...

PT-2026-50832

Name of the Vulnerable Software and Affected Versions libexpat versions prior to 2.8.2 Description A heap-based buffer overflow occurs in the doProlog function within xmlparse.c. This issue arises because the reallocation of the scaffold backing array is mishandled when data-structure sharing is...

Astra Linux – Vulnerabilities in Firefox, Thunderbird, Expat, LibXMLTok

The addBinding method in xmlparse.c within Expat also known as libexpat has an integer overflow issue before version 2.4.3...

Astra Linux – Vulnerabilities in Firefox, Thunderbird, and Expat

The issue with integer overflow occurs in storeAtts in the xmlparse.c file, within the Expat library also known as libexpat, before version 2.4.3...

Astra Linux – Vulnerabilities in Firefox, Thunderbird, and Expat

The defineAttribute function in xmlparse.c of Expat also known as libexpat has an integer overflow before version 2.4.3...

Astra Linux – Vulnerability in Firefox, expat, libxmltok, Thunderbird

The libexpat library before version 2.4.9 has a use-after-free issue in the doContent function of the xmlparse.c file...

Astra Linux – Vulnerabilities in Firefox, Thunderbird, and Expat

The nextScaffoldPart function in xmlparse.c of Expat also known as libexpat, prior to version 2.4.3, has an integer overflow issue...

Astra Linux – Vulnerabilities in Firefox, Thunderbird, and Expat

The buildmodel function in xmlparse.c within ExPat also known as libexpat has an integer overflow issue before version 2.4.3...

Unity Linux 20.1060e / 20.1070e Security Update: expat (UTSA-2026-017360)

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-017360 advisory. In doProlog in xmlparse.c in Expat aka libexpat before 2.4.3, an integer overflow exists for mgroupSize. Tenable has extracted the preceding description block direct...

Unity Linux 20.1060e / 20.1070e Security Update: expat (UTSA-2026-017358)

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-017358 advisory. defineAttribute in xmlparse.c in Expat aka libexpat before 2.4.3 has an integer overflow. Tenable has extracted the preceding description block directly from the Uni...

Unity Linux 20.1060e / 20.1070e Security Update: expat (UTSA-2026-017361)

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-017361 advisory. nextScaffoldPart in xmlparse.c in Expat aka libexpat before 2.4.3 has an integer overflow. Tenable has extracted the preceding description block directly from the...

Unity Linux 20.1060e / 20.1070e Security Update: expat (UTSA-2026-017354)

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-017354 advisory. storeAtts in xmlparse.c in Expat aka libexpat before 2.4.3 has an integer overflow. Tenable has extracted the preceding description block directly from the Unity Lin...