An exploitable vulnerability exists in the grsecurity PaX patch for the function read_kmem, in PaX from version pax-linux-4.9.8-test1 to 4.9.24-test7, grsecurity official from version grsecurity-3.1-4.9.8-201702060653 to grsecurity-3.1-4.9.24-201704252333, grsecurity unofficial from version v4.9.25-unofficialgrsec to v4.9.74-unofficialgrsec. PaX adds a temp buffer to the read_kmem function, which is never freed when an invalid address is supplied. This results in a memory leakage that can lead to a crash of the system. An attacker needs to induce a read to /dev/kmem using an invalid address to exploit this vulnerability.
The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Grsecurity | Opensrcsec | 3.1-4.9.8-201702060653 (including) | 3.1-4.9.24-201704252333 (including) |
| Grsecurity | Opensrcsec | 4.9.25 (including) | 4.9.74 (including) |
| Pax | Opensrcsec | pax-linux-4.9.8-test1 (including) | pax-linux-4.9.8-test7 (including) |