CVE-2022-49077

CVE-2022-49077 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-193.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: mmmremap.c: avoid pointless invalidate_range_start/end on mremap(old_size=0) If an mremap() syscall with old_size=0 ends up in move_page_tables(), it will call invalidate_range_start()/invalidate_range_end() unnecessarily, i.e. with an empty range. This causes a WARN in KVM's mmu_notifier. In the past, empty ranges have been diagnosed to be off-by-one bugs, hence the WARNing. Given the low (so far) number of unique reports, the benefits of detecting more buggy callers seem to outweigh the cost of having to fix cases such as this one, where userspace is doing something silly. In this particular case, an early return from move_page_tables() is enough to fix the issue.

Frequently asked questions

What is CVE-2022-49077?
In the Linux kernel, the following vulnerability has been resolved: mmmremap.c: avoid pointless invalidate_range_start/end on mremap(old_size=0) If an mremap() syscall with old_size=0 ends up in move_page_tables(), it will call invalidate_range_start()/invalidate_range_end() unnecessarily, i.e. with an empty range. This causes a WARN in KVM's mmu_notifier. In the past, empty ranges have been diagnosed to be off-by-one bugs, hence the WARNing. Given the low (so far) number of unique reports, the benefits of detecting more buggy callers seem to outweigh the cost of having to fix cases such as this one, where userspace is doing something silly. In this particular case, an early return from move_page_tables() is enough to fix the issue.
How severe is CVE-2022-49077?
CVE-2022-49077 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-2022-49077 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-49077?
CVE-2022-49077 primarily affects Linux Linux Kernel. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-49077?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2022-49077 have an EU (EUVD) identifier?
Yes. CVE-2022-49077 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2022-55127.
When was CVE-2022-49077 published?
CVE-2022-49077 was published on 2025-02-26 and last updated on 2026-06-17.

References

Affected products (2)

More vulnerabilities in Linux Linux Kernel

All CVEs affecting Linux Linux Kernel →

Other CWE-193 (Off-by-one Error) vulnerabilities

Browse all CWE-193 (Off-by-one Error) vulnerabilities →