daphne: Unauthenticated attackers can cause excessive memory consumption by sending arbitrarily large WebSocket messages/framesGHSA-rrc9-mx66-ffcm
MEDIUMGHSA-rrc9-mx66-ffcm is a medium-severity (CVSS 5.3) CWE-770 vulnerability in daphne. A fix is available for daphne — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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-rrc9-mx66-ffcm.
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
daphneReal-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
daphne before 4.2.2 did not pass maxFramePayloadSize or maxMessagePayloadSize to Autobahn's WebSocketServerFactory. Because Autobahn defaults both values to 0 (unlimited), an unauthenticated remote attacker could send arbitrarily large WebSocket messages or frames, causing excessive memory consumption and a denial of service.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | daphne | all versions | 4.2.2pip install --upgrade 'daphne==4.2.2' |
Affected Products
daphnedjangoprojectDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for daphne, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update daphne to 4.2.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-rrc9-mx66-ffcm is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
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 |
|---|---|---|
| Red Hat Ansible Automation Platform 2.5 for RHEL 8 | python3.12-daphne-0:4.2.2-1.el8ap | RHSA-2026:50319 |
| Red Hat Ansible Automation Platform 2.6 for RHEL 9 | python3.12-daphne-0:4.2.2-1.el9ap | RHSA-2026:50336 |
| Red Hat Ansible Automation Platform 2.6 for RHEL 9 | automation-controller-0:4.7.16-1.el9ap | RHSA-2026:59136 |
| Red Hat Ansible Automation Platform 2.5 | ansible-automation-platform-25/lightspeed-rhel8:1785430174 | RHSA-2026:50357 |
| Red Hat Ansible Automation Platform 2.6 | ansible-automation-platform-26/eda-controller-rhel9:1785633038 | RHSA-2026:50479 |
| Red Hat Ansible Automation Platform 2.6 | ansible-automation-platform-26/controller-rhel9:1787244009 | RHSA-2026:59155 |
| Red Hat Ansible Automation Platform 2.7 | ansible-automation-platform-27/eda-controller-rhel9:1785374869 | RHSA-2026:50340 |
| Red Hat Ansible Automation Platform 2.7 | ansible-automation-platform-27/controller-rhel9:1787220257 | RHSA-2026:59153 |
Frequently Asked Questions
Is GHSA-rrc9-mx66-ffcm in your dependencies?
Find it across PyPI, including transitive dependencies.