CVE Feed

    Dashboard / CVE / CVE-2026-86143

    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.

    Published:Sep 5, 2026
    Last Modified:Sep 8, 2026
    EPS:Sep 5, 2026
    EPSS Score:0.00119
    CVSS Score:6.9

    Affected Products

    Vendor
    Xmlsoft
    Product
    Libxml2

    Exploits

    No exploit reference

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-92 Forced Integer Overflow

    Related CVEs

    CVE-2026-86144 (CVSS 5.6) — In xinclude in libxml2 before 2.15.4, xmlXIncludeProcess and xmlXIncludeProcessTree do not propagate parseFlag…
    CVE-2026-86142 (CVSS 6.9) — In libxml2 before 2.15.4, there is a heap-based buffer overflow in xmlXPtrEvalXPtrPart because of xmlXPtrEval …
    CVE-2026-86141 (CVSS 2.9) — xmlregexp in libxml2 before 2.15.4 has a NULL pointer dereference in xmlRegNewParserCtxt after a strdup failur…
    CVE-2026-86140 (CVSS 8) — In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.…
    CVE-2026-86139 (CVSS 6.9) — In libxml2 before 2.15.4, xmlURIEscapeStr in uri.c has an integer overflow.…
    CVE-2026-86138 (CVSS 6.9) — In libxml2 before 2.15.4, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer …
    CVE-2026-86137 (CVSS 2.9) — In libxml2 before 2.15.4, xmlFAParsePosCharGroup has an out-of-bounds read, aka an out-of-bounds read in the N…
    CVE-2026-11979 (CVSS 1.8) — libxml2 is vulnerable to multiple stack-based buffer overflows in the xmlcatalog utility when running in --she…
    CVE-2026-6732 (CVSS 6.5) — A flaw was found in libxml2. This vulnerability occurs when the library processes a specially crafted XML Sche…
    CVE-2025-9714 (CVSS 6.2) — Uncontrolled recursion in XPath evaluation in libxml2 up to and including version 2.9.14 allows a local attack…

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High