rclone serve s3: --auth-proxy without --auth-key authenticates nobody - full SigV4 signature bypass

Date Sep 10, 2026
Type Vendor advisory
Signal High-risk advisory
Vendor / Product Go ยท github.com/rclone/rclone
CVE CVE-2026-88018
High-risk advisory CVE-2026-88018

Summary

rclone serve s3: --auth-proxy without --auth-key authenticates nobody - full SigV4 signature bypass

Why it matters

GitHub has published a reviewed security advisory for github.com/rclone/rclone. Prioritize it with other application dependency updates.

Operator check

Check whether github.com/rclone/rclone is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available.

Sources

PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.