CVE-2026-78633 Okta CVE debrief

Who should care

Okta RADIUS Agent administrators and security teams handling authentication requests should assess exposure and prioritize verification and potential updates. This includes reviewing the current version of the Okta RADIUS Agent, checking for and applying updates, and implementing compensating controls if necessary. Security teams should also focus on monitoring and detecting potential exploitation attempts and have incident response plans in place.

Why it matters

Defenders should prioritize verifying exposure of Okta RADIUS Agent instances, especially those handling authentication requests, and assess the need for updates or compensating controls due to a denial-of-service vulnerability.

• Denial of new RADIUS authentication requests due to worker-thread exhaustion
• Potential disruption to authentication services
• Need for verification of Okta RADIUS Agent version and exposure
• Possible impact on system availability and authentication reliability

Technical summary

The Okta RADIUS Agent does not validate sub-attribute lengths when parsing Vendor-Specific attributes. A sub-attribute length of zero causes the parser to loop indefinitely, resulting in worker-thread exhaustion and denial of new RADIUS authentication requests. This technical issue arises from the lack of validation in the packet parser, which can lead to denial-of-service attacks. Defenders should focus on verifying exposure and assessing the need for updates or compensating controls based on official advisories and CVE details.

Defensive priority

Defenders should prioritize verifying exposure of Okta RADIUS Agent instances, especially those handling authentication requests, and assess the need for updates or compensating controls.

Recommended defensive actions

• Verify Okta RADIUS Agent version and check for updates to 2.28.0 or later
• Assess exposure of Okta RADIUS Agent instances, especially those handling authentication requests
• Implement compensating controls, such as rate limiting or monitoring, if updates are not feasible
• Review 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
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed

Evidence notes

The CVE Program record and NVD vulnerability detail provide official information on the vulnerability. Okta's security advisory offers supplemental details on the issue. Evidence is limited to public sources, and defenders should verify the vulnerability's impact within their environments. The Okta RADIUS Agent's packet parser vulnerability allows for potential denial-of-service attacks, and defenders should review the official advisory for affected versions and update guidance.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.