A use-after-free vulnerability in the Linux Kernel traffic control index filter (tcindex) can be exploited to achieve local privilege escalation. The tcindex_delete function which does not properly deactivate filters in case of a perfect hashes while deleting the underlying structure which can later lead to double freeing the structure. A local attacker user can use this vulnerability to elevate its privileges to root. We recommend upgrading past commit 8c710f75256bb3cf05ac7b1672c82b92c43f3d28.
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
| Link | Tags |
|---|---|
| https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=8c710f75256bb3cf05ac7b1672c82b92c43f3d28 | patch mailing list |
| https://kernel.dance/#8c710f75256bb3cf05ac7b1672c82b92c43f3d28 | patch |
| https://lists.debian.org/debian-lts-announce/2023/05/msg00005.html | third party advisory mailing list |
| https://lists.debian.org/debian-lts-announce/2023/05/msg00006.html | third party advisory mailing list |
| https://security.netapp.com/advisory/ntap-20230601-0001/ | third party advisory |