GHSA-9rpw-2h95-666c
HIGHGHSA-9rpw-2h95-666c is a high-severity (CVSS 7.5) Improper Input Validation vulnerability in github.com/cloudflare/goflow/v3. O3 Security confirms whether GHSA-9rpw-2h95-666c is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cloudflare GoFlow vulnerable to a Denial of Service in the sflow packet handling package
Blast Radius
github.com/cloudflare/goflow/v3Real-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
Impact
The sflow decode package prior to version 3.4.4 does not employ sufficient packet sanitisation which can lead to a denial of service attack. Attackers can craft malformed packets causing the process to consume huge amounts of memory resulting in a denial of service.
Specific Go Packages Affected
github.com/cloudflare/goflow/v3/decoders/sflow
Patches
Version 3.4.4 contains patches fixing this.
Workarounds
A possible workaround is to not have your goflow collector publicly reachable.
For more information
If you have any questions or comments about this advisory:
- Open an issue in goflow repo
- Email us netdev[@]cloudflare.com
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/cloudflare/goflow/v3 | all versions | 3.4.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cloudflare/goflow/v3. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/cloudflare/goflow/v3 to 3.4.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9rpw-2h95-666c 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 pinpoints whether GHSA-9rpw-2h95-666c is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-9rpw-2h95-666c. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-9rpw-2h95-666c in your dependencies?
O3 detects GHSA-9rpw-2h95-666c across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.