Misleading kernel logs via syscall-as-syndrome confusion
Published Feb 26, 2025 · Updated Aug 15, 2026
Improper diagnostic handling in Linux kernel arm64 compat code allows local users to print misleading exception messages via invalid syscalls. compat_arm_syscall stores an attacker-chosen syscall number in thread.fault_code, and arm64_show_signal misinterprets its high bits as an ESR_ELx exception class. A 32-bit arm64 compatibility process must invoke an unknown syscall below 0x80000000; the consequence is false exception context in kernel logs.
Summary
What happened
Improper diagnostic handling in Linux kernel arm64 compat code allows local users to print misleading exception messages via invalid syscalls. compat_arm_syscall stores an attacker-chosen syscall number in thread.fault_code, and arm64_show_signal misinterprets its high bits as an ESR_ELx exception class. A 32-bit arm64 compatibility process must invoke an unknown syscall below 0x80000000; the consequence is false exception context in kernel logs.
The record
- CVE
- CVE-2022-49520
- Published
- Feb 26, 2025
- Updated
- Aug 15, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 26, 2025CVE publishedPublication date reported by the CVE source.
- Aug 15, 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=4.17
- Affected versionversion=532826f3712b607256eb30f92f23d1c604d3fa34 <095e975f8150ccd7f852eb578c1cdbdd2f517c7a
- Affected versionversion=532826f3712b607256eb30f92f23d1c604d3fa34 <3910ae71cb963fa2b68e684489d4fc3d105afda0
- Affected versionversion=532826f3712b607256eb30f92f23d1c604d3fa34 <3fed9e551417b84038b15117732ea4505eee386b
- Affected versionversion=532826f3712b607256eb30f92f23d1c604d3fa34 <621916afe8cd4f322eb12759b64a2f938d4e551d
- Affected versionversion=532826f3712b607256eb30f92f23d1c604d3fa34 <ad97425d23af3c3b8d4f6a2bb666cb485087c007
- Affected versionversion=532826f3712b607256eb30f92f23d1c604d3fa34 <efd183d988b416fcdf6f7c298a17ced4859ca77d
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
No sourced classifications are available.
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