CVE-2026-86139

libxml2 before 2.15.4 contains an integer overflow in the xmlURIEscapeStr function within uri.c. The upstream fix (commit 8edbbdb0) adds a zero-length guard after xmlStrlen to catch cases where the function returns 0 for a non-empty input, preventing the overflow. According to Red Hat, the flaw c...

CVE-2026-86144

libxml2 versions before 2.15.4 contain a flaw in the XInclude processing functions xmlXIncludeProcess and xmlXIncludeProcessTree , which fail to propagate parser flags such as XML_PARSE_NONET . When a custom resource loader is used, this allows network access during XInclude expansion, potentiall...

CVE-2026-86143

libxml2 before 2.15.4 has an integer overflow in the xmlIO module. An inconsistency between xmlOutputWriteCallback and xmlBufUse causes negative length values to reach downstream write callbacks when data backlogs exceed maximum integer limits (approximately 2 GiB ). This can lead to data corrupt...

CVE-2026-86141

libxml2 versions before 2.15.4 contain a NULL pointer dereference in the xmlregexp module, specifically in the xmlRegNewParserCtxt function. The root cause is a missing string length calculation after a strdup failure and NULL check, leading to a potential crash. The CVSS 3.1 score is 2.9 (Low) w...