Affected: AlmaLinux:9: libxml2, AlmaLinux:9: libxml2-devel, AlmaLinux:9: python3-libxml2

The libxml2 library is a development toolbox providing the implementation of various XML standards.

Security Fix(es):

* libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow (CVE-2026-86138) * libxml2: libxml2: Data integrity issues due to integer overflow in write callbacks (CVE-2026-86143) * libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements (CVE-2026-86140) * libxml2: libxml2: Heap-based buffer overflow in xmlXPtrEval due to xpointer length saturation (CVE-2026-86142) * libxml2: libxml2: Information disclosure, SSRF, or denial of service due to improper parseFlags propagation. (CVE-2026-86144) * libxml2: double-free/UAF in libxml2 Python bindings (CVE-2026-74860)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Affected: Alpaquita:25: libxml2, Alpaquita:stream: libxml2, BellSoft Hardened Containers:25: libxml2, BellSoft Hardened Containers:stream: libxml2

In xmlIO in libxml2 before 2.15.4, an inconsistency in xmlOutputWriteCallback and xmlBufUse causes negative lengths to reach write callbacks, aka a lack of a check for integer overflow before calling writecallback. This has security relevance for many types of uses of that length value within a callback.

In xmlIO in libxml2 before 2.15.4, an inconsistency in xmlOutputWriteCallback and xmlBufUse causes negative lengths to reach write callbacks, aka a lack of a check for integer overflow before calling writecallback. This has security relevance for many types of uses of that length value within a callback.

libxml2: double-free/UAF in libxml2 Python bindings libxml2: libxml2: Denial of Service via out-of-bounds read in xmlFAParsePosCharGroup libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow libxml2: libxml2: Integer overflow in xmlURIEscapeStr may lead to arbitrary code execution libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements libxml2: libxml2: Denial of Service due to NULL pointer dereference in xmlRegNewParserCtxt libxml2: libxml2: Heap-based buffer overflow in xmlXPtrEval due to xpointer length saturation libxml2: libxml2: Data integrity issues due to integer overflow in write callbacks libxml2: libxml2: Information disclosure, SSRF, or denial of service due to improper parseFlags propagation.

libxml2: double-free/UAF in libxml2 Python bindings libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements libxml2: libxml2: Heap-based buffer overflow in xmlXPtrEval due to xpointer length saturation libxml2: libxml2: Data integrity issues due to integer overflow in write callbacks libxml2: libxml2: Information disclosure, SSRF, or denial of service due to improper parseFlags propagation.

Affected: Rocky Linux:9: libxml2

The libxml2 library is a development toolbox providing the implementation of various XML standards.

Security Fix(es):

* libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow (CVE-2026-86138)

* libxml2: libxml2: Data integrity issues due to integer overflow in write callbacks (CVE-2026-86143)

* libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements (CVE-2026-86140)

* libxml2: libxml2: Heap-based buffer overflow in xmlXPtrEval due to xpointer length saturation (CVE-2026-86142)

* libxml2: libxml2: Information disclosure, SSRF, or denial of service due to improper parseFlags propagation. (CVE-2026-86144)

* libxml2: double-free/UAF in libxml2 Python bindings (CVE-2026-74860)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Affected: Ubuntu:Pro:14.04:LTS: libxml2, Ubuntu:Pro:16.04:LTS: libxml2, Ubuntu:Pro:18.04:LTS: libxml2, Ubuntu:Pro:20.04:LTS: libxml2, Ubuntu:22.04:LTS: libxml2, Ubuntu:24.04:LTS: libxml2, Ubuntu:26.04:LTS: libxml2

In xmlIO in libxml2 before 2.15.4, an inconsistency in xmlOutputWriteCallback and xmlBufUse causes negative lengths to reach write callbacks, aka a lack of a check for integer overflow before calling writecallback. This has security relevance for many types of uses of that length value within a callback.

Ein Angreifer kann mehrere Schwachstellen in libxml2 ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um Daten zu manipulieren oder offenzulegen und um einen Denial of Service herbeizuführen.