Privilege escalation via unchecked EIOINTC CPU index
Published Jul 25, 2025 · Updated Aug 5, 2026
Out-of-bounds access in Linux KVM 6.13 through 6.15.4 allows local users to read or overwrite kernel memory through EIOINTC ioctls. kvm_eiointc_regs_access() derives a CPU index from attr->attr and indexes coreisr.reg_u32 without checking the index against s->num_cpu before copying four bytes to or from user space. Access requires a local account able to open /dev/kvm and create an EIOINTC device; exploitation enables kernel-memory disclosure, corruption, host crashes, or privilege escalation.
Summary
What happened
Out-of-bounds access in Linux KVM 6.13 through 6.15.4 allows local users to read or overwrite kernel memory through EIOINTC ioctls. kvm_eiointc_regs_access() derives a CPU index from attr->attr and indexes coreisr.reg_u32 without checking the index against s->num_cpu before copying four bytes to or from user space. Access requires a local account able to open /dev/kvm and create an EIOINTC device; exploitation enables kernel-memory disclosure, corruption, host crashes, or privilege escalation.
The record
- CVE
- CVE-2025-38366
- Published
- Jul 25, 2025
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 25, 2025CVE publishedPublication date reported by the CVE source.
- Aug 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1ad7efa552fd5cf4e8c49fea863c5c6a5dcf9f00 <a3293b4078ee93174f70f36d3ab7618554ce6ab6
- Affected versionversion=1ad7efa552fd5cf4e8c49fea863c5c6a5dcf9f00 <cc8d5b209e09d3b52bca1ffe00045876842d96ae
- Affected versionversion=6.13
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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