CVE-2026-79787 Alluxio CVE debrief

Who should care

Defenders responsible for Alluxio deployments, especially those using the S3 REST proxy, should assess exposure and implement signature verification to prevent unauthorized access.

Why it matters

CVE-2026-79787 is a critical vulnerability in Alluxio's S3 REST proxy that allows unauthenticated attackers to spoof user identity and access sensitive data. Defenders should prioritize verifying and mitigating the vulnerability to prevent data breaches.

• Unauthenticated attackers can spoof user identity to access sensitive data.
• Attackers can read, write, and delete arbitrary data without proper authentication.
• Defenders need to verify and mitigate the vulnerability to prevent data breaches.
• Remediation priority is high due to the critical CVSS score of 9.3.

Technical summary

Alluxio's S3 REST proxy fails to verify AWS Signature Version 4 signatures in its default configuration, allowing unauthenticated attackers to spoof user identity and read, write, and delete arbitrary data. The vulnerability has a critical CVSS score of 9.3, indicating high severity. The CVE record and NVD entry provide details about the vulnerability, but specific details about affected versions and remediation steps are limited. Defenders should prioritize verifying and mitigating the vulnerability to prevent data breaches.

Defensive priority

Defenders should prioritize verifying and mitigating the vulnerability in Alluxio's S3 REST proxy, especially in configurations where AWS Signature Version 4 signatures are not verified.

Recommended defensive actions

• Verify if the Alluxio S3 REST proxy is in use and if AWS Signature Version 4 signatures are not verified.
• Implement signature verification for the S3 REST proxy if not already done.
• Monitor for unauthorized access attempts to the Alluxio system.
• Review and update access controls to prevent unauthorized data access.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Evidence notes

The CVE record and NVD entry provide details about the vulnerability in Alluxio's S3 REST proxy. However, specific details about affected versions and remediation steps are limited. The vulnerability allows unauthenticated attackers to spoof user identity and access sensitive data. Defenders should verify and mitigate the vulnerability to prevent data breaches. The CVE record was published on 2026-08-25T19:16:54.907Z and has not been modified since then. The NVD entry provides additional information about the vulnerability and its CV

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.