CVE-2026-99223EPSS p5.7%
CVE-2026-99223CVE-2026-99223
Description
In the Linux kernel, the following vulnerability has been resolved:
keys: make keyring indexes independent of kernel addresses
KEYCTL_READ returns the serial numbers in a keyring in associative-array
traversal order. The first word of the index is a public, deterministic
hash of the type pointer, domain pointer and description. An unprivileged
user can therefore insert keys with known descriptions, predict their
order for each possible KASLR slide, and recover the kernel image address.
On an x86-64 build with 16 MiB alignment, 45 user keys suffice to
distinguish the candidate slides.
Remove the addresses from the whole index, not just its first hash word.
Assign each key type and domain a nonzero 64-bit ID and hash those IDs and
the description with a once-initialized SipHash key. Use the full IDs in
the later index chunks as well. Truncating or hashing the IDs there would
lose the guarantee that distinct type/domain/description tuples have a
differing index bit.
Allocate IDs l
Scoring
| EPSS | 0.17% probability of exploitation · percentile 5.7% · 2026-11-03T12:00:27Z |
| Last modified | 2026-11-03 |