CVE-2026-63278: Package URLs can be used to exfiltrate arbitrary INI file values and environment variables
URLs could be constructed which expanded environment variable or INI file values, so potentially sensitive information could be exfiltrated to a remote server on opening a document containing such links. The check added for CVE-2024-12426 did not recognise every way of naming the package content provider, so a URL that named it differently still reached the expansion. In fixed versions the package content provider is matched when the URL is checked.
Affected Software
Event History
Frequently Asked Questions
What interaction is required for exploitation?
A target must open a document containing a crafted link. The link can cause values to be expanded and sent to a remote server.
Does the earlier check for CVE-2024-12426 fully protect against this issue?
No. That check did not recognize every way of naming the package content provider, allowing differently named URLs to still reach the expansion.
What changes in fixed versions?
Fixed versions match the package content provider when checking the URL, preventing the naming variation that bypassed the earlier check.