CVE-2021-22556: Integer Overflow in Fuchsia Kernel

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-05-03 · updated 2026-06-17
Weakness: CWE-190

Description

The Security Team discovered an integer overflow bug that allows an attacker with code execution to issue memory cache invalidation operations on pages that they don’t own, allowing them to control kernel memory from userspace. We recommend upgrading to kernel version 4.1 or beyond.

Affected products

Google LLC Fuchsia Kernel: before 4.1 — fixed in 4.1

How to fix

Upgrade to a fixed version: Google LLC Fuchsia Kernel 4.1. Check the vendor advisory for mitigations.

References

https://fuchsia-review.googlesource.com/c/fuchsia/+/570881
https://fuchsia.dev/whats-new/release-notes/f4-1
https://fuchsia-review.googlesource.com/c/fuchsia/+/570881
https://fuchsia.dev/whats-new/release-notes/f4-1

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