Host denial of service via hypercall misclassification
Published Jan 11, 2025 · Updated May 23, 2026
Improper hypercall handling in affected Linux KVM kernels allows guest OS users to interrupt host availability via VMGEXIT. complete_hypercall_exit() calls is_64_bit_mode() even when SEV-ES or SEV-SNP hides the vCPU state needed by that test, so a 64-bit hypercall is misclassified. A protected AMD guest able to issue KVM_HC_MAP_GPA_RANGE through VMGEXIT can reach the path and trigger a host-kernel warning.
Summary
What happened
Improper hypercall handling in affected Linux KVM kernels allows guest OS users to interrupt host availability via VMGEXIT. complete_hypercall_exit() calls is_64_bit_mode() even when SEV-ES or SEV-SNP hides the vCPU state needed by that test, so a 64-bit hypercall is misclassified. A protected AMD guest able to issue KVM_HC_MAP_GPA_RANGE through VMGEXIT can reach the path and trigger a host-kernel warning.
The record
- CVE
- CVE-2024-55881
- Published
- Jan 11, 2025
- Updated
- May 23, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jan 11, 2025CVE publishedPublication date reported by the CVE source.
- May 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=5.15.5 <5.15.176
- Affected versionversion=5.16
- Affected versionversion=5969e2435cbd7f0ce8c28d717bfc39987ee8d8f1 <0840d360a8909c722fb62459f42836afe32ededb
- Affected versionversion=b5aead0064f33ae5e693a364e3204fe1c0ac9af2 <22b5c2acd65dbe949032f619d4758a35a82fffc3
- Affected versionversion=b5aead0064f33ae5e693a364e3204fe1c0ac9af2 <3d2634ec0d1dbe8f4b511cf5261f327c6a76f4b6
- Affected versionversion=b5aead0064f33ae5e693a364e3204fe1c0ac9af2 <7ed4db315094963de0678a8adfd43c46471b9349
- Affected versionversion=b5aead0064f33ae5e693a364e3204fe1c0ac9af2 <9b42d1e8e4fe9dc631162c04caa69b0d1860b0f0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo