Security readout for executives and security teams
Plain-English summary
A malicious or compromised host can manipulate a Linux TDX guest’s attestation response length, causing the guest to expose memory beyond its allocated quote buffer. That data may be forwarded to an attestation service and could cross container boundaries. Systems not using TDX guest attestation are unlikely to be exposed.
Executive priority
Prioritize affected TDX attestation environments, especially confidential workloads hosted outside the organization’s direct trust boundary. Expedite vendor-confirmed kernel updates where sensitive guest memory or multi-container isolation is at stake. Ordinary Linux systems without TDX quote generation are not the primary concern.
Technical view
The tdx-guest quote path trusted host-controlled quote_buf->out_len and was vulnerable to oversized lengths or races while consuming the response. This could produce an out-of-bounds read beyond allocated quote_buf pages, up to TSM_REPORT_OUTBLOB_MAX, into guest userspace. The referenced kernel changes validate the length and response consistency.
Likely exposure
Exposure is limited to affected Linux kernels running Intel TDX guests that request remote-attestation quotes. Risk is greater where the host is untrusted or compromised, attestation output is forwarded externally, or per-container configfs-tsm-report interfaces are available. The supplied version data does not clearly establish complete vulnerable and fixed release ranges.
Exploitation context
The supplied sources do not report active exploitation, and this CVE is not listed as KEV in the bundle. Exploitation requires influence over the host-provided TDX quote response. The documented consequences are guest-memory disclosure and possible availability impact; no public exploit evidence is supplied.
Researcher notes
The flaw is a host-controlled length-validation and response-race issue in the tdx-guest quote path. Quotes are not private, but adjacent guest memory unintentionally copied with them may be sensitive. The bundle provides four stable-kernel commits but no CWE, proof of concept, exploitation report, or unambiguous release-range mapping.
Mitigation direction
- Update to a vendor-supported Linux kernel containing the applicable referenced stable fix.
- Confirm the fixed kernel version with your distribution or platform vendor before rollout.
- Until updated, restrict or disable unnecessary TDX quote-reporting interfaces where operationally feasible.
- Limit untrusted container access to per-container configfs-tsm-report interfaces.
Validation and detection
- Inventory Linux TDX guests and identify workloads using remote-attestation quote generation.
- Record running kernel versions and compare them with vendor advisories and referenced stable commits.
- Review whether quote output is forwarded to external attestation services.
- Check whether containers receive separate configfs-tsm-report interfaces or related access.
- After updating, verify the running kernel includes the applicable length-validation fix.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
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Container behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-31470 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H1.85.2LinuxVulnerability scoring details
Base CVSS 3.1 score
7.1HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
Source materials
- CVE List V5 sourceCVE List V5
- https://git.kernel.org/stable/c/a079a62883e3365de592cea9f7a669d8115433b0CVE reference, Linux
- https://git.kernel.org/stable/c/6f3c8795ae9ba74fa10fe979293d1904712d3fb1CVE reference, Linux
- https://git.kernel.org/stable/c/02ca2d9d197723696cb9cc0cb159eb7e8bf5f89bCVE reference, Linux
- https://git.kernel.org/stable/c/c3fd16c3b98ed726294feab2f94f876290bf7b61CVE reference, Linux
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.