CVE-2021-25834 is a high-severity (CVSS 7.5) CWE-294 vulnerability in github.com/cosmos/ethermint. A fix is available for github.com/cosmos/ethermint — see the affected versions and patch details below.
Authentication bypass by capture-replay in github.com/cosmos/ethermint
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2021-25834 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
github.com/cosmos/ethermintReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Cosmos Network Ethermint <= v0.4.0 is affected by a transaction replay vulnerability in the EVM module. If the victim sends a very large nonce transaction, the attacker can replay the transaction through the application.
Specific Go Packages Affected
github.com/cosmos/ethermint/rpc/namespaces/eth
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/cosmos/ethermint | all versions | 0.4.1go get github.com/cosmos/ethermint@v0.4.1 |
Affected Products
ethermintchainsafeDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cosmos/ethermint, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/cosmos/ethermint to 0.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-25834 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2021-25834 in your dependencies?
Find it across Go, including transitive dependencies.