CSIRTS // UNIFIED SECURITY ADVISORY FEEDSYS ● ONLINE · POWERED BY INTELFUSIONS.COM

CSIRTSSecurity advisory fusion

← All products

libexpat — security advisories

12 advisories1 sourcelatest 2026-06-09⚡ RSS feed

Every advisory CSIRTS.com has correlated to libexpat, newest first — across national CERTs, vendor PSIRTs and vulnerability databases.

⚡ Watch libexpat

Get an email when a new libexpat advisory drops — max one per day, one-click unsubscribe.

CVE-2026-56406: libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.

mediumCVSS 6.9CVE-2026-56406msrc2026-06-09

CVE-2026-56409: xmlwf in libexpat before 2.8.2 has an integer overflow for the output filename when -d outputDir is used.

mediumCVSS 6.5CVE-2026-56409msrc2026-06-09

CVE-2026-56405: libexpat before 2.8.2 has an integer overflow in getAttributeId.

mediumCVSS 6.9CVE-2026-56405msrc2026-06-09

CVE-2026-56411: xmlwf in libexpat before 2.8.2 has an integer overflow in endDoctypeDecl via NOTATION declarations.

mediumCVSS 6.9CVE-2026-56411msrc2026-06-09

CVE-2026-56131: libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation. Thus, a use-after-free can occur (similar to the CVE-2026-50219 situation).

mediumCVSS 4.9CVE-2026-56131msrc2026-06-09

CVE-2026-50219: libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation. Thus, a use-after-free can occur,

mediumCVSS 4.9CVE-2026-50219msrc2026-06-09

CVE-2026-56410: xmlwf in libexpat before 2.8.2 has an integer overflow in resolveSystemId.

mediumCVSS 6.9CVE-2026-56410msrc2026-06-09

CVE-2026-56412: libexpat before 2.8.2 does not consider XML_TOK_DATA_CHARS in doCdataSection and thus lacks handler call depth tracking for various calls from within handlers in cases of a policy violation. Thus, a use-after-free can occur. NOTE: this issue exists because of an incomplete fix for CVE-2026-50219.

mediumCVSS 4.9CVE-2026-56412msrc2026-06-09

CVE-2026-56403: libexpat before 2.8.2 has an integer overflow in storeAtts.

mediumCVSS 6.9CVE-2026-56403msrc2026-06-09

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.

mediumCVSS 6.9CVE-2026-56132msrc2026-06-09

CVE-2026-56404: libexpat before 2.8.2 has an integer overflow in addBinding.

mediumCVSS 6.9CVE-2026-56404msrc2026-06-09

CVE-2026-56407: libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.

mediumCVSS 6.9CVE-2026-56407msrc2026-06-09