libxml2-2.9.7-21.el8_10.9

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: 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.

CVE-2026-74860
A flaw was found in libxml2 with Python bindings enabled. A remote attacker could exploit this vulnerability by providing a specially crafted XML document containing a Document Type Definition (DTD) with enumerated attribute values. This triggers a double-free error in the SAX attributeDecl callback handler, where a string is freed twice. This flaw can lead to a denial of service (DoS) due to a reproducible crash in Python applications using the libxml2 SAX bindings.
CVE-2026-86138
In libxml2 before 2.15.4, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
CVE-2026-86140
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
CVE-2026-86143
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.
CVE-2026-86144
In xinclude in libxml2 before 2.15.4, xmlXIncludeProcess and xmlXIncludeProcessTree do not propagate parseFlags. This has security relevance for, for example, the XML_PARSE_NONET flag, if (without it) a custom resource loader accesses the internet and triggers XML external entity injection, SSRF, or a denial of service (e.g., for an attacker-controlled internet resource that is intentionally slow).