dcap-qvl: Improper Certificate Validation
CVE-2026-22696 is a critical-severity improper certificate validation vulnerability in dcap-qvl from Phala-Network, with a CVSS 4.0 base score of 9.3 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected dcap-qvl versions: < 0.3.9. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.21% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of dcap-qvl you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Phala-Network | dcap-qvl | < 0.3.9 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- NoneThe attack does not depend on a particular deployment or configuration.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- HighSerious loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- HighSerious loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- NoneNo loss of availability on the vulnerable system.
- Confidentiality (other systems)
- NoneNo loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- NoneNo loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- NoneNo loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (github.com).
Official description
dcap-qvl implements the quote verification logic for DCAP (Data Center Attestation Primitives). A vulnerability present in versions prior to 0.3.9 involves a critical gap in the cryptographic verification process within the dcap-qvl. The library fetches QE Identity collateral (including qe_identity, qe_identity_signature, and qe_identity_issuer_chain) from the PCCS. However, it skips to verify the QE Identity signature against its certificate chain and does not enforce policy constraints on the QE Report. An attacker can forge the QE Identity data to whitelist a malicious or non-Intel Quoting Enclave. This allows the attacker to forge the QE and sign untrusted quotes that the verifier will accept as valid. Effectively, this bypasses the entire remote attestation security model, as the verifier can no longer trust the entity responsible for signing the quotes. All deployments utilizing the dcap-qvl library for SGX or TDX quote verification are affected. The vulnerability has been patched in dcap-qvl version 0.3.9. The fix implements the missing cryptographic verification for the QE Identity signature and enforces the required checks for MRSIGNER, ISVPRODID, and ISVSVN against the QE Report. Users of the `@phala/dcap-qvl-node` and `@phala/dcap-qvl-web` packages should switch to the pure JavaScript implementation, `@phala/dcap-qvl`. There are no known workarounds for this vulnerability. Users must upgrade to the patched version to ensure that QE Identity collateral is properly verified.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Certificate Validation
The product does not validate, or incorrectly validates, a certificate.
How developers prevent this class of flaw
- Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
- If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.
More Improper Certificate Validation vulnerabilities (CWE-295)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Recent Improper Certificate Validation vulnerabilities
- 9.8 Critical severity
- 7.4 High severity
- 8.8 High severity
- 7.4 High severity
- 7.4 High severity
- 9.1 Critical severity
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