CVE-2021-41135 Authz Module Non-Determinism

What is CVE-2021-41135?

CVE-2021-41135 is a medium-severity denial of service vulnerability in cosmos-sdk, published on 20 Oct 2021. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

The Cosmos-SDK is a framework for building blockchain applications in Golang. Affected versions of the SDK were vulnerable to a consensus halt due to non-deterministic behaviour in a ValidateBasic method in the x/authz module. The MsgGrant of the x/authz module contains a Grant field which includes a user-defined expiration time for when the authorization grant expires. In Grant.ValidateBasic(), that time is compared to the node’s local clock time. Any chain running an affected version of the SDK with the authz module enabled could be halted by anyone with the ability to send transactions on that chain. Recovery would require applying the patch and rolling back the latest block. Users are advised to update to version 0.44.2.

Weakness: CWE-754

Which versions are affected by CVE-2021-41135?

2 open source packages ship an affected version, including github.com/cosmos/cosmos-sdk. It affects 1 product.

Products include Interchain Cosmos Sdk.

How do I fix CVE-2021-41135?

Upgrade github.com/cosmos/cosmos-sdk to 0.44.2 or later.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-41135 being exploited?

There is no known exploitation of CVE-2021-41135 in the wild and no public exploit code.

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-2p6r-37p9-89p2.