CVE Catalog

CVE-2026-53343

MediumCVSS 5.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.11%

2th percentile - higher than 2% of all known CVEs

Summary

In the Linux kernel for ARM architecture, there is an issue in __switch_to() related to KASAN VMAP stack shadow. The ldr instruction was used to read the stack shadow, which is byte-granular and may not be word-aligned, causing an alignment fault on ARMv5.

Risk Assessment

The risk is a system crash (alignment exception) on older ARM processors (ARMv5) with CONFIG_KASAN_VMALLOC and CONFIG_VMAP_STACK enabled, preventing boot.

Recommendation

It is recommended to update the Linux kernel to a version containing the fix that uses ldrb (load byte) instead of ldr for KASAN shadow access.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: ARM: 9475/1: entry: use byte load for KASAN VMAP stack shadow Commit 44e9a3bb76e5 ("ARM: 9430/1: entry: Do a dummy read from VMAP shadow") added a dummy read from the KASAN VMAP stack shadow in __switch_to(). The read uses ldr, but the KASAN shadow address is byte-granular and is not guaranteed to be word aligned. ARMv5 faults unaligned word loads. With CONFIG_KASAN_VMALLOC and CONFIG_VMAP_STACK enabled, ARM926/VersatilePB crashes in __switch_to() with an alignment exception before reaching init. Use ldrb for the dummy shadow access. The code only needs to fault in the shadow mapping if the stack shadow is missing, so a byte load is sufficient and matches the granularity of KASAN shadow memory.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS