Evervault Go SDK: Incomplete PCR Validation in Enclave Attestation for non-Evervault hosted Enclaves

### Summary A vulnerability was identified in the `evervault-go` SDK’s attestation verification logic that may allow incomplete documents to pass validation. This may cause the client to trust an enclave operator that does not meet expected integrity guarantees. The exploitability of this issue is limited in Evervault-hosted environments as an attacker would require the pre-requisite ability to serve requests from specific evervault domain names, following from our ACME challenge based TLS certificate acquisition pipeline. The vulnerability primarily affects applications which only check PCR8. Though the efficacy is also reduced for applications that check all PCR values, the impact is largely remediated by checking PCR 0, 1 and 2. ### Patches The identified issue has been addressed in version [1.3.2](https://github.com/evervault/evervault-go/pull/48) by validating attestation documents before storing in the cache, and replacing the naive equality checks with a new SatisfiedBy check. ### Workarounds If you are using evervault-go to attest Enclaves that are hosted outside of Evervault environments and cannot upgrade: 1) Modify your application logic to fail verification if PCR8 is not explicitly present and non-empty 2) Add custom pre-validation to reject documents that omit any required PCRs. ### POC ``` package evervault import ( "testing" "github.com/evervault/evervault-go/attestation" "github.com/stretchr/testify/assert" "github.com/hf/nitrite" ) func TestVulnerableCompare(t *testing.T) { assert := assert.New(t) // arrange expectedPCRs := []attestation.PCRs{ attestation.PCRs{ PCR0: "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001", PCR1: "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002", PCR2: "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003", PCR8: "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004", }, } actualDocument := nitrite.Document {} actualDocument.PCRs = map[uint][]byte{ 10: make([]byte, 32), } // act v := verifyPCRs(expectedPCRs, actualDocument) // assert // Verify should not pass but it does assert.Equal(true, v) } ```

Source published

12 Nov 2025 21:45:06 UTC

Source modified

18 Nov 2025 17:00:18 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N

Publisher rating · HIGH