CVE-2020-12439 is a medium-severity (CVSS 5.3) CWE-404 vulnerability in grin. A fix is available for grin — see the affected versions and patch details below.
Grin allows attackers to adversely affect availability of data on a Mimblewimble blockchain
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
grinReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Grin before 3.1.0 allows attackers to adversely affect availability of data on a Mimblewimble blockchain.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | grin | all versions | 3.1.0cargo update -p grin --precise 3.1.0 |
Affected Products
gringrinDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for grin, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update grin to 3.1.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-12439 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-2020-12439 in your dependencies?
Find it across crates.io, including transitive dependencies.