CVE-2026-104030 Red Hat CVE debrief

Who should care

Authentication service administrators, security teams, and system administrators responsible for maintaining sssd installations should care about this vulnerability. They should assess exposure, verify system vulnerability, and apply patches or workarounds as needed. The vulnerability can disrupt authentication services, and defenders should review the context and verify the vulnerability. The affected operator is the authentication service administrator,

Why it matters

CVE-2026-104030 is a medium-severity vulnerability in sssd that allows a local user to cause a Denial of Service (DoS). Defenders should assess exposure and verify system vulnerability, as the vulnerability can disrupt authentication services.

• Potential disruption of authentication services
• Need for verification of system vulnerability and exposure
• Potential for increased monitoring and logging of authentication service activity

Technical summary

A flaw in sssd allows a local user to cause a Denial of Service (DoS) by submitting a specially crafted passkey authentication token lacking null terminators, causing the authentication service to crash and disrupting authentication services. The vulnerability affects sssd installations, and defenders should assess exposure and verify system vulnerability. The technical impact is a disruption of authentication services, and the source-grounded technical framing is related to passkey authentication token handling. The CVE record and NVD entry provide details on the vulnerability, but specific version information and remediation steps are not provided.

Defensive priority

Medium priority for authentication service administrators and security teams to assess exposure and verify system vulnerability.

Recommended defensive actions

• Assess exposure of authentication services to local users
• Verify system vulnerability and apply patches or workarounds as needed
• Monitor authentication service logs for potential exploitation attempts
• 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
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, but specific version information and remediation steps are not provided. The evidence is limited to the information available in the CVE record and NVD entry. Defenders should verify the affected scope, severity, and vendor guidance. The vulnerability affects sssd installations, and defenders should assess exposure and verify system vulnerability.

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.