Local privilege escalation via unsupported user-fence write
Published Jul 19, 2026 · Updated Jul 19, 2026
Memory corruption in the AMDGPU JPEG v4.0 ring in Linux Kernel allows local users to escalate privileges through a crafted command submission. amdgpu_cs_ioctl accepts an AMDGPU_CHUNK_ID_FENCE user fence for a ring that supports only 32-bit writes, while amdgpu_ib.c emits a 64-bit fence to an attacker-chosen GPU address. A local unprivileged user needs render-node access and affected RDNA3-class hardware; exploitation permits information disclosure, arbitrary writes, kernel code execution, or a GPU hang or reset.
Summary
What happened
Memory corruption in the AMDGPU JPEG v4.0 ring in Linux Kernel allows local users to escalate privileges through a crafted command submission. amdgpu_cs_ioctl accepts an AMDGPU_CHUNK_ID_FENCE user fence for a ring that supports only 32-bit writes, while amdgpu_ib.c emits a 64-bit fence to an attacker-chosen GPU address. A local unprivileged user needs render-node access and affected RDNA3-class hardware; exploitation permits information disclosure, arbitrary writes, kernel code execution, or a GPU hang or reset.
The record
- CVE
- CVE-2026-63845
- Published
- Jul 19, 2026
- Updated
- Jul 19, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 19, 2026CVE publishedPublication date reported by the CVE source.
- Jul 19, 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=5.19
- Affected versionversion=b13111de32a9202c6d58bb7e4c06296b99c4d7e3 <6876d05b899102f4dfdb9ad560132126144c1c72
- Affected versionversion=b13111de32a9202c6d58bb7e4c06296b99c4d7e3 <a676f16ea9a7df96d69f405afb6eb349571b3382
- Affected versionversion=b13111de32a9202c6d58bb7e4c06296b99c4d7e3 <af4b458daa597dae707bf3f1f74745f5fc133ca2
- Affected versionversion=b13111de32a9202c6d58bb7e4c06296b99c4d7e3 <d4e0172a1b614373385e9b7111b580f8d2e0b98f
- Affected versionversion=b13111de32a9202c6d58bb7e4c06296b99c4d7e3 <e7e90b5839aeb8805ec83bb4da610b8dab8e184d
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