What’s Vulnerable › Vulnerabilities

CVE-2022-49556: KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak

• Severity: high (CVSS 7.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-02-26 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak For some sev ioctl interfaces, the length parameter that is passed maybe less than or equal to SEV_FW_BLOB_MAX_SIZE, but larger than the data that PSP firmware returns. In this case, kmalloc will allocate memory that is the size of the input rather than the size of the data. Since PSP firmware doesn't fully overwrite the allocated buffer, these sev ioctl interface may return uninitialized kernel slab memory.

Affected products

• Linux kernel: from 5.7 before 5.10.124; from 5.11 before 5.15.45; from 5.16 before 5.17.13; from 5.18 before 5.18.2 — fixed in 5.10.124, 5.15.45, 5.17.13, 5.18.2

How to fix

Upgrade to a fixed version: Linux kernel 5.10.124, 5.15.45, 5.17.13, 5.18.2. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/401bef1f95de92c3a8c6eece46e02fa88d7285ee
• https://git.kernel.org/stable/c/57a01725339f9d82b099102ba2751621b1caab93
• https://git.kernel.org/stable/c/bbdcc644b59e01e98c68894a9fab42b9687f42b0
• https://git.kernel.org/stable/c/d22d2474e3953996f03528b84b7f52cc26a39403
• https://git.kernel.org/stable/c/d8fdb4b24097472ff6b3c0559448200d420b1418

Get alerted when CVE-2022-49556 or the next vulnerability affects your stack