Improper certificate validation for some Intel(R) TDX Workload Attestation software within Ring 3: User Applications may allow an escalation of privilege. Unprivileged software adversary with an unauthenticated user combined with a low complexity attack may enable data manipulation. This result may potentially occur via local access when attack requirements are present without special internal knowledge and requires no user interaction. The potential vulnerability may impact the confidentiality (none), integrity (high) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (none), integrity (none) and availability (none) impacts.
Improper certificate validation for some Intel(R) TDX Workload Attestation software within Ring 3: User Applications may allow an escalation of privilege. Unprivileged software adversary with an unauthenticated user combined with a low complexity attack may enable data manipulation. This result may potentially occur via local access when attack requirements are present without special internal knowledge and requires no user interaction. The potential vulnerability may impact the confidentiality (none), integrity (high) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (none), integrity (none) and availability (none) impacts.
Improper certificate validation for some Intel(R) TDX Workload Attestation software within Ring 3: User Applications may allow an escalation of privilege. Unprivileged software adversary with an unauthenticated user combined with a low complexity attack may enable data manipulation. This result may potentially occur via local access when attack requirements are present without special internal knowledge and requires no user interaction. The potential vulnerability may impact the confidentiality (none), integrity (high) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (none), integrity (none) and availability (none) impacts.
`tdx_workload_attestation::verification::x509::verify_x509_cert()`, available
with the `host-verification` feature, checked that `issuer_cert` issued `cert`
and verified the certificate signature. It did not check the certificate's
validity period, so it accepted expired and not-yet-valid certificates.
With the `host-gcp-tdx` feature, this function validates the GCP launch
endorsement signing certificate against the GCE confidential-computing TCB
root certificate. A signing certificate outside its validity period was
therefore still accepted during launch endorsement verification.
Intel describes the issue as improper certificate validation and classifies
it as escalation of privilege, with a CVSS 4.0 base score of 5.9, in
INTEL-SA-01520.
The flaw was corrected in
[#86](https://github.com/IntelLabs/tdx-workload-attestation/pull/86), released
in 0.2.0. The function now returns `Ok(false)` when the current time is
outside the certificate's `notBefore`/`notAfter` range.
Reported by [Borys Tsyrulnikov](https://borystsyrulnikov.dev).
EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.
Original publisher date fields
datePublished: Nov 10, 2026, 4:30:50 PM
dateUpdated: Nov 11, 2026, 10:48:01 AM
No normalized affected-package data is projected for this source revision. The original publisher record may contain additional product and version evidence; this does not establish that a package is unaffected.
NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.
Source analysis status: Awaiting Analysis
Weakness classifications: CWE-295
Original publisher date fields
published: 2026-11-10T17:17:43.447
lastModified: 2026-11-11T11:17:20.233
No normalized affected-package data is projected for this source revision. The original publisher record may contain additional product and version evidence; this does not establish that a package is unaffected.