That one sounds squarely on Nvidia. Any driver that uses undocumented workarounds to gain kernel level access or utilizes an access loophool for system hooks is a bad driver. I'd assume Debian, or likely more accurately the Linux kernel itself was updated following some matter of CVE that Nvidia was quietly abusing.

Frustrating, but a good example of why those kinds of proprietary drivers are such a nightmare. You really just don't know what techniques they're using.