PatchSiren cyber security CVE debrief
CVE-2026-54490 faye CVE debrief
CVE-2026-54490 is a denial of service vulnerability in websocket-driver, a WebSocket protocol handler with pluggable I/O. The issue occurs when using the permessage-deflate extension, allowing WebSocket servers or clients to accept messages larger than the configured maximum message size. This can lead to applications accepting larger messages than expected and exceeding their intended resource usage. Users of websocket-driver should be aware of this vulnerability and take steps to mitigate it, especially those using the permessage-deflate extension.
- Vendor
- faye
- Product
- websocket-driver-node
- CVSS
- MEDIUM 6.3
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-07-17
- Original CVE updated
- 2026-07-17
- Advisory published
- 2026-07-17
- Advisory updated
- 2026-07-17
Who should care
Users of websocket-driver, especially those using the permessage-deflate extension, should be aware of this vulnerability and take steps to mitigate it. This includes reviewing and adjusting configuration for maximum message size and monitoring for unusual traffic patterns. Security teams and operators using websocket-driver should prioritize patching and compensating controls.
Technical summary
The vulnerability occurs because the library checks the limit against the message frames' length headers, which give the size of the compressed data, not the size after decompression. This oversight can lead to applications accepting larger messages than expected and exceeding their intended resource usage. The issue is fixed in version 0.7.5 of websocket-driver. Users should review configurations and monitor traffic to mitigate potential impacts, especially when using the permessage-deflate extension. Affected deployments should prioritize patching and compensating controls, and verify accuracy of information to assess exposure.
Defensive priority
Medium priority due to CVSS score of 6.3 and potential for denial of service attacks.
Recommended defensive actions
- Update websocket-driver to version 0.7.5 or later
- Review and adjust configuration for maximum message size
- Monitor for unusual traffic patterns
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
- Review compensating controls for exposed systems while remediation is scheduled and verified
- Check relevant monitoring, detection, and logs for exposed assets that need extra review
- Track exceptions, retest remediated assets, and close the item only after evidence is documented
Evidence notes
Evidence is based on official CVE and NVD records, as well as source references from GitHub. The CVE record was published on 2026-07-17T21:17:08.780Z and has not been modified since then. No additional information is available about the vulnerability beyond what is provided in these records. However, defenders should verify the accuracy of this information and assess their own exposure to the vulnerability.
Official resources
AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-17T21:17:08.780Z and has not been modified since then.