CVE-2026-79787
Authentication bypass
- Published25 Aug 2026
Description
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 3.1 breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HRemediation
No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.
References
- 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
Related CVEs
Recent high-severity vulnerabilities sharing a weakness type.
Frequently asked
Is CVE-2026-79787 being actively exploited?
CVE-2026-79787 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.46%.
How severe is CVE-2026-79787?
CVE-2026-79787 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.46% probability of exploitation.
How do I fix CVE-2026-79787?
Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.
How Secuno handles this
Secuno correlates vulnerabilities like CVE-2026-79787 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.
Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.