| CVE-2026-76957 | ALTO7.8 | libexpat before 2.8.4 lacks handler call depth tracking with custom encoding callbacks. Thus, a use-after-free can occur. NOTE: this is similar to CVE-2026-50219, CVE-2026-56131 and CVE-2026-56412. | 20/08/2026 |
| CVE-2026-76956 | ALTO7.5 | In libexpat 2.8.2 and 2.8.3 before 2.8.4, misinterpretation of getentropy's return code leads to insufficient entropy, which results in being vulnerable to hash flooding attacks, causing a denial of service via crafted XML content. | 20/08/2026 |
| CVE-2026-66046 | ALTO7.5 | Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementType->defaultAtts to determine CDATA status. A remote unauthent | 18/08/2026 |
| CVE-2026-56412 | MEDIO5.9 | 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. | 21/06/2026 |
| CVE-2026-56411 | MEDIO6.9 | xmlwf in libexpat before 2.8.2 has an integer overflow in endDoctypeDecl via NOTATION declarations. | 21/06/2026 |
| CVE-2026-56410 | MEDIO6.9 | xmlwf in libexpat before 2.8.2 has an integer overflow in resolveSystemId. | 21/06/2026 |
| CVE-2026-56409 | MEDIO6.5 | xmlwf in libexpat before 2.8.2 has an integer overflow for the output filename when -d outputDir is used. | 21/06/2026 |
| CVE-2026-56408 | MEDIO6.9 | libexpat before 2.8.2 has an integer overflow in copyString. | 21/06/2026 |
| CVE-2026-56407 | MEDIO6.9 | libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen. | 21/06/2026 |
| CVE-2026-56406 | MEDIO6.9 | libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse. | 21/06/2026 |
| CVE-2026-56405 | MEDIO6.9 | libexpat before 2.8.2 has an integer overflow in getAttributeId. | 21/06/2026 |
| CVE-2026-56404 | MEDIO6.9 | libexpat before 2.8.2 has an integer overflow in addBinding. | 21/06/2026 |
| CVE-2026-56403 | MEDIO6.9 | libexpat before 2.8.2 has an integer overflow in storeAtts. | 21/06/2026 |
| CVE-2026-56132 | MEDIO6.9 | 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. | 19/06/2026 |
| CVE-2026-56131 | MEDIO4.9 | 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). | 19/06/2026 |
| CVE-2026-50219 | MEDIO5.9 | 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, | 04/06/2026 |
| CVE-2026-45186 | ALTO7.5 | In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input. | 10/05/2026 |
| CVE-2026-41080 | BAJO2.9 | libexpat before 2.8.0 uses insufficient entropy, and thus hash flooding can occur via a crafted XML document. | 16/04/2026 |
| CVE-2026-32778 | MEDIO5.5 | libexpat before 2.7.5 allows a NULL pointer dereference in the function setContext on retry after an earlier ouf-of-memory condition. | 16/03/2026 |
| CVE-2026-32777 | MEDIO5.5 | libexpat before 2.7.5 allows an infinite loop while parsing DTD content. | 16/03/2026 |