by Kastro
Paper/Archive/CVE-2026-79787

CVE-2026-79787

Alluxio alluxio — Alluxio through 2.9.5 S3 REST Proxy Authentication Bypass via Unverified Request Signature

EPSS 0.5%public exploitCVSS 9.8
critical.is priorityof 100
47
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 39.5.395 × 207.9Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
alluxio≤ 2.9.5–CNA

Scores by source

VulnCheck (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

refgithub.com/Alluxio/alluxioexploitgithub.com/Alluxio/alluxio/issues/18755writeupgithub.com/Alluxio/alluxio/blob/v2.9.5/core/server/proxy/src/main/java/alluxio/proxy/s3/S3RestUtils.javawriteupvulncheck.com/advisories/alluxio-through-2.9.5-s3-rest-proxy-authentication-bypass-via-unverified-request-signature