Description

In the Linux kernel, the following vulnerability has been resolved:

crypto: arm64/neonbs - fix out-of-bounds access on short input

The bit-sliced implementation of AES-CTR operates on blocks of 128
bytes, and will fall back to the plain NEON version for tail blocks or
inputs that are shorter than 128 bytes to begin with.

It will call straight into the plain NEON asm helper, which performs all
memory accesses in granules of 16 bytes (the size of a NEON register).
For this reason, the associated plain NEON glue code will copy inputs
shorter than 16 bytes into a temporary buffer, given that this is a rare
occurrence and it is not worth the effort to work around this in the asm
code.

The fallback from the bit-sliced NEON version fails to take this into
account, potentially resulting in out-of-bounds accesses. So clone the
same workaround, and use a temp buffer for short in/outputs.

Classification

CVE ID: CVE-2024-26789

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.05% (probability of being exploited)

EPSS Percentile: 17.83% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

https://git.kernel.org/stable/c/034e2d70b5c7f578200ad09955aeb2aa65d1164a
https://git.kernel.org/stable/c/1291d278b5574819a7266568ce4c28bce9438705
https://git.kernel.org/stable/c/9e8ecd4908b53941ab6f0f51584ab80c6c6606c4
https://git.kernel.org/stable/c/1c0cf6d19690141002889d72622b90fc01562ce4

Timeline