Headline
GHSA-r2h5-3hgw-8j34: User data in TPM attestation vulnerable to MITM
Impact
Attestation user data (such as the digest of the public key in an aTLS connection) was bound to the issuer’s TPM, but not to its PCR state. An attacker could intercept a node initialization, initialize the node themselves, and then impersonate an uninitialized node to the validator. In practice, this meant that a CSP insider with sufficient privileges would have been able to join a node under their control to a Constellation cluster.
Patches
The issue has been patched in v2.5.2.
Workarounds
none
Package
gomod github.com/edgelesssys/constellation/v2 (Go)
Affected versions
<= 2.5.1
Description
Impact
Attestation user data (such as the digest of the public key in an aTLS connection) was bound to the issuer’s TPM, but not to its PCR state. An attacker could intercept a node initialization, initialize the node themselves, and then impersonate an uninitialized node to the validator. In practice, this meant that a CSP insider with sufficient privileges would have been able to join a node under their control to a Constellation cluster.
Patches
The issue has been patched in v2.5.2.
Workarounds
none
References
- GHSA-r2h5-3hgw-8j34
- https://github.com/edgelesssys/constellation/releases/tag/v2.5.2
Published to the GitHub Advisory Database
Feb 17, 2023