CVE-2022-49726

CVE-2022-49726 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-908.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: clocksource: hyper-v: unexport __init-annotated hv_init_clocksource() EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic. modpost used to detect it, but it has been broken for a decade. Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds. There are two ways to fix it: - Remove __init - Remove EXPORT_SYMBOL I chose the latter for this case because the only in-tree call-site, arch/x86/kernel/cpu/mshyperv.c is never compiled as modular. (CONFIG_HYPERVISOR_GUEST is boolean)

Frequently asked questions

What is CVE-2022-49726?
In the Linux kernel, the following vulnerability has been resolved: clocksource: hyper-v: unexport __init-annotated hv_init_clocksource() EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic. modpost used to detect it, but it has been broken for a decade. Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds. There are two ways to fix it: - Remove __init - Remove EXPORT_SYMBOL I chose the latter for this case because the only in-tree call-site, arch/x86/kernel/cpu/mshyperv.c is never compiled as modular. (CONFIG_HYPERVISOR_GUEST is boolean)
How severe is CVE-2022-49726?
CVE-2022-49726 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2022-49726 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-49726?
CVE-2022-49726 primarily affects Linux Linux Kernel. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-49726?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2022-49726 have an EU (EUVD) identifier?
Yes. CVE-2022-49726 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2022-54509.
When was CVE-2022-49726 published?
CVE-2022-49726 was published on 2025-02-26 and last updated on 2026-06-17.

References

Affected products (3)

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