CVE-2026-41066

Affected versions of the lxml package are vulnerable to XML External Entity Injection due to insecure default parser configuration that resolves external entities. The iterparse() function and the ETCompatXMLParser() class both default to resolve_entities=True, so untrusted XML input processed through either parser will expand external entity references and read referenced local files from the host. An attacker who supplies a crafted XML document to an application using these parsers in their default configuration can read sensitive local files and exfiltrate their contents through the parsed output.