On Mon, Jun 15, 2020 at 6:24 PM John Haxby <john.haxby@xxxxxxxxxx> wrote: > > On 15 Jun 2020, at 11:26, Jason A. Donenfeld <Jason@xxxxxxxxx> wrote: > > Yesterday, I found a lockdown bypass in Ubuntu 18.04's kernel using > > ACPI table tricks via the efi ssdt variable [1]. Today I found another > > one that's a bit easier to exploit and appears to be unpatched on > > mainline, using acpi_configfs to inject an ACPI table. The tricks are > > basically the same as the first one, but this one appears to be > > unpatched, at least on my test machine. Explanation is in the header > > of the PoC: > > > > https://git.zx2c4.com/american-unsigned-language/tree/american-unsigned-language-2.sh > > > > I need to get some sleep, but if nobody posts a patch in the > > meanwhile, I'll try to post a fix tomorrow. > > > > Jason > > > > [1] https://www.openwall.com/lists/oss-security/2020/06/14/1 > > > This looks CVE-worthy. Are you going to ask for a CVE for it? Does it really make sense to dole out CVEs for individual lockdown bypasses when various areas of the kernel (such as filesystems and BPF) don't see root->kernel privilege escalation issues as a problem? It's not like applying the fix for this one issue is going to make systems meaningfully safer.
