Apache Commons Net vulnerable to information leakage via malicious serverGHSA-cgp8-4m63-fhh5
MEDIUMFix: apache/commons-net@4fe1baeGHSA-cgp8-4m63-fhh5 is a medium-severity (CVSS 6.5) Improper Input Validation vulnerability in commons-net:commons-net. A fix is available for commons-net:commons-net — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-cgp8-4m63-fhh5.
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
commons-net:commons-netReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Prior to Apache Commons Net 3.9.0, Net's FTP client trusts the host from PASV response by default. A malicious server can redirect the Commons Net code to use a different host, but the user has to connect to the malicious server in the first place. This may lead to leakage of information about services running on the private network of the client. The default in version 3.9.0 is now false to ignore such hosts, as cURL does. See https://issues.apache.org/jira/browse/NET-711.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | commons-net:commons-net | all versions | 3.9.0commons-net:commons-net:3.9.0 |
Affected Products
commons netapachedebian linuxdebianDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for commons-net:commons-net, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update commons-net:commons-net to 3.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-cgp8-4m63-fhh5 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.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| RHINT Camel-Q 2.13.3 | apache-commons-net | RHSA-2023:3667 |
| RHINT Camel-Springboot 3.20.1 | apache-commons-net | RHSA-2023:2100 |
Frequently Asked Questions
Is GHSA-cgp8-4m63-fhh5 in your dependencies?
Find it across Maven, including transitive dependencies.