Xmldom · Xmldom · CVE-2021-21366
**Name of the Vulnerable Software and Affected Versions**
xmldom versions 0.4.0 and older
**Description**
The issue arises when xmldom versions 0.4.0 and older fail to correctly preserve system identifiers, FPIs, or namespaces when repeatedly parsing and serializing maliciously crafted documents. This may lead to unexpected syntactic changes during XML processing in some downstream applications.
**Recommendations**
For versions 0.4.0 and older, update to version 0.5.0.
As a temporary workaround, downstream applications can validate the input and reject the maliciously crafted documents.