GHSA-3rq5-2g8h-59hc is a medium-severity (CVSS 5.9) CWE-292 vulnerability in eventlet. A fix is available for eventlet — see the affected versions and patch details below.
Potential DoS via the Tudoor mechanism in eventlet and dnspython
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-3rq5-2g8h-59hc.
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
GHSA-3rq5-2g8h-59hc 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 379,145 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
eventlet🐍dnspythonReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
eventlet before 0.35.2, as used in dnspython before 2.6.0, allows remote attackers to interfere with DNS name resolution by quickly sending an invalid packet from the expected IP address and source port, aka a "TuDoor" attack. In other words, dnspython does not have the preferred behavior in which the DNS name resolution algorithm would proceed, within the full time window, in order to wait for a valid packet. NOTE: dnspython 2.6.0 is unusable for a different reason that was addressed in 2.6.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | eventlet | all versions | 0.35.2pip install --upgrade 'eventlet==0.35.2' |
| 🐍PyPI | dnspython | all versions | 2.6.1pip install --upgrade 'dnspython==2.6.1' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for eventlet, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update eventlet to 0.35.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3rq5-2g8h-59hc 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 GHSA-3rq5-2g8h-59hc can be triaged on real exposure rather than presence alone.
Tailored to GHSA-3rq5-2g8h-59hc. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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.
The vulnerability in dnspython where it may accept a malicious DNS response over a legitimate one due to timing issues poses a moderate severity risk. While the impact is limited to potential denial of service for DNS resolution requests, it requires precise timing and the ability to send malicious responses before…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Ansible Automation Platform 2.4 for RHEL 8 | ansible-automation-platform-24/ee-supported-rhel8:1.0.0-661 | RHSA-2024:3483 |
| Red Hat Enterprise Linux 8 | python-dns-0:1.15.0-12.el8_10 | RHSA-2024:3275 |
| Red Hat Enterprise Linux 9 | python-dns-0:2.6.1-3.el9 | RHSA-2024:9423 |
| Red Hat OpenShift Container Platform 4.13 | openshift4/ose-ironic-rhel9:v4.13.0-202407230838.p0.g0456ffe.assembly.stream.el9 | RHSA-2024:4846 |
| Red Hat OpenShift Container Platform 4.14 | openshift4/ose-ironic-rhel9:v4.14.0-202407301840.p0.g2d4e89c.assembly.stream.el9 | RHSA-2024:4960 |
| Red Hat OpenShift Container Platform 4.15 | openshift4/ose-ironic-rhel9:v4.15.0-202407181606.p0.gea6d005.assembly.stream.el9 | RHSA-2024:4699 |
| Red Hat OpenShift Container Platform 4.16 | python-eventlet-0:0.33.1-6.el9 | RHSA-2024:0045 |
Frequently Asked Questions
Is GHSA-3rq5-2g8h-59hc in your dependencies?
O3 Security finds GHSA-3rq5-2g8h-59hc across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.