CVE-2019-3564 is a high-severity (CVSS 7.5) CWE-834 vulnerability in github.com/facebook/fbthrift. A fix is available for github.com/facebook/fbthrift — see the affected versions and patch details below.
Improper Input Validation and Excessive Iteration in Go Facebook Thrift
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2019-3564 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/facebook/fbthriftReal-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
Go Facebook Thrift servers would not error upon receiving messages with containers of fields of unknown type. As a result, malicious clients could send short messages which would take a long time for the server to parse, potentially leading to denial of service. This issue affects Facebook Thrift prior to v2019.03.04.00.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/facebook/fbthrift | all versions | 0.31.1-0.20190225164308-c461c1bd1a3ego get github.com/facebook/fbthrift@v0.31.1-0.20190225164308-c461c1bd1a3e |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/facebook/fbthrift, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/facebook/fbthrift to 0.31.1-0.20190225164308-c461c1bd1a3e or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-3564 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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2019-3564 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2019-3564. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2019-3564 in your dependencies?
O3 Security finds CVE-2019-3564 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.