CVE-2021-41135
Authz Module Non-Determinism
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Authz Module Non-Determinism
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.
- Record
CVE-2021-41135- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- Updated
- 2026-11-02
EUVDEUVD-2021-2140
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.
- Record
EUVD-2021-2140- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-2p6r-37p9-89p2
Authz Module Non-Determinism
Impact
Consensus failure for 0.43.x and 0.44.{0,1} users. Funds and balances are safe.
Patches
0.44.2
Workarounds
Manually patch the code.
Full details posted in https://forum.cosmos.network/t/cosmos-sdk-vulnerability-retrospective-security-advisory-jackfruit-october-12-2021/5349.
- Record
GHSA-2p6r-37p9-89p2- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2021-41135- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 4.0 Medium
AV:N/AC:L/Au:S/C:N/I:N/A:P - Weakness
- CWE-754
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2021-41135- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVGHSA-2p6r-37p9-89p2
Authz Module Non-Determinism
Impact
Consensus failure for 0.43.x and 0.44.{0,1} users. Funds and balances are safe.
Patches
0.44.2
Workarounds
Manually patch the code.
Full details posted in https://forum.cosmos.network/t/cosmos-sdk-vulnerability-retrospective-security-advisory-jackfruit-october-12-2021/5349.
- Record
GHSA-2p6r-37p9-89p2- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/cosmos/cosmos-sdkGo |
0.43.0 up to 0.44.2 | 0.44.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-41135 is a medium vulnerability (CVSS 6.5) in Cosmos Cosmos-sdk, published October 20, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.71%, the 77th percentile. Fixed in github.com/cosmos/cosmos-sdk 0.44.2.
References
github.com/cosmos/cosmos-sdk/security/advisories/GHSA-2p6r-37p9-89p2
forum.cosmos.network/t/cosmos-sdk-vulnerability-retrospective-security-advisory-jackfruit-october-12-2021/5349
nvd.nist.gov/vuln/detail/CVE-2021-41135