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.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
| Link | Tags |
|---|---|
| https://www.varnish-cache.org/security/VSV00012.html | patch vendor advisory |
| https://docs.varnish-software.com/security/VSV00012/ | mitigation vendor advisory |
| https://github.com/varnish/libvmod-digest/releases/tag/libvmod-digest-1.0.3 | release notes |