CVE-2026-79787

Alluxio's S3 REST proxy fails to verify AWS Signature Version 4 signatures in its default configuration, allowing unauthenticated attackers to spoof user identity. Attackers can extract usernames from unsigned Authorization headers and impersonate any user, including service accounts, to read, write, and delete arbitrary data.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/Alluxio/alluxio
https://github.com/Alluxio/alluxio/blob/v2.9.5/core/server/proxy/src/main/java/alluxio/proxy/s3/S3RestUtils.java
https://github.com/Alluxio/alluxio/issues/18755
https://www.vulncheck.com/advisories/alluxio-through-2.9.5-s3-rest-proxy-authentication-bypass-via-unverified-request-signature
https://github.com/Alluxio/alluxio/issues/18755

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 19:16

Updated : 2026-08-25 19:16

NVD link : CVE-2026-79787

Mitre link : CVE-2026-79787

CVE.ORG link : CVE-2026-79787

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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