What’s Vulnerable › Vulnerabilities

CVE-2025-40266: KVM: arm64: Check the untrusted offset in FF-A memory share

• Severity: high (CVSS 8.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-12-04 · updated 2026-10-18

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Check the untrusted offset in FF-A memory share Verify the offset to prevent OOB access in the hypervisor FF-A buffer in case an untrusted large enough value [U32_MAX - sizeof(struct ffa_composite_mem_region) + 1, U32_MAX] is set from the host kernel.

Affected products

• Linux kernel: 3.11 — fixed in 6.18

How to fix

Upgrade to a fixed version: Linux kernel 6.18. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/103e17aac09cdd358133f9e00998b75d6c1f1518
• https://git.kernel.org/stable/c/bc1909ef38788f2ee3d8011d70bf029948433051
• https://git.kernel.org/stable/c/f9f1aed6c8a3427900da3121e1868124854569c3
• https://git.kernel.org/stable/c/fc3139d9f4c1fe1c7d5f25f99676bd8e9c6a1041

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