Kernel memory disclosure via unchecked quote length
Published Apr 22, 2026 · Updated Apr 22, 2026
Out-of-bounds read in the Linux kernel TDX guest driver allows attackers to expose guest kernel memory through attestation quotes. The driver trusts host-controlled quote_buf->out_len while copying a quote to guest userspace, so an oversized or raced value reads beyond allocated quote pages. Exploitation requires a TDX guest requesting remote-attestation quotes from a malicious host; leaked data can cross container boundaries or reach an attestation server.
Summary
What happened
Out-of-bounds read in the Linux kernel TDX guest driver allows attackers to expose guest kernel memory through attestation quotes. The driver trusts host-controlled quote_buf->out_len while copying a quote to guest userspace, so an oversized or raced value reads beyond allocated quote pages. Exploitation requires a TDX guest requesting remote-attestation quotes from a malicious host; leaked data can cross container boundaries or reach an attestation server.
The record
- CVE
- CVE-2026-31470
- Published
- Apr 22, 2026
- Updated
- Apr 22, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-787
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 22, 2026CVE publishedPublication date reported by the CVE source.
- Apr 22, 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?
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- Affected versionversion=6.7
- Affected versionversion=f4738f56d1dc62aaba69b33702a5ab098f1b8c63 <02ca2d9d197723696cb9cc0cb159eb7e8bf5f89b
- Affected versionversion=f4738f56d1dc62aaba69b33702a5ab098f1b8c63 <6f3c8795ae9ba74fa10fe979293d1904712d3fb1
- Affected versionversion=f4738f56d1dc62aaba69b33702a5ab098f1b8c63 <a079a62883e3365de592cea9f7a669d8115433b0
- Affected versionversion=f4738f56d1dc62aaba69b33702a5ab098f1b8c63 <c3fd16c3b98ed726294feab2f94f876290bf7b61
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What is affected?
Published CVSS scores
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Attacks
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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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