eParakstītājs 3.0 for Windows before version
1.10.0 retrieves and executes its automatic updates over a channel that is not
authenticated or integrity-protected. On each launch the application fetches an
update descriptor (XML) over TLS but accepts any TLS certificate (a permissive
TrustManager and a HostnameVerifier that always returns true), does not verify
any digital signature on the update descriptor, and does not verify the
Authenticode signature or a checksum of the downloaded installer before running
it. A man-in-the-middle attacker able to redirect www.eparaksts.lv can serve a
crafted update descriptor pointing to an attacker-controlled executable, which
the client downloads and executes, resulting in arbitrary code execution on the
victim host.
Until updated, disable
automatic updates and install new versions only from the official signed
package obtained over a trusted network, verifying the Authenticode signature
manually.
Update eParakstītājs 3.0 to
version 1.10.0 or later, in which the update channel is authenticated and the
downloaded installer is signature-verified.