The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

libvmod-digest before 1.0.3, as used in Varnish Enterprise 6.0.x before 6.0.11r5, has an out-of-bounds memory access during base64 decoding, leading to both authentication bypass and information disclosure; however, the exact attack surface will depend on the particular VCL (Varnish Configuration Language) configuration in use.