{"cve":"CVE-2026-88018","nvd":{"published":"2026-09-10T16:18:08.913","modified":"2026-09-14T20:01:05.627","status":"Analyzed","description":"rclone is a command-line program to sync files and directories to and from different cloud storage providers. Prior to 1.75.1, rclone serve s3 configured with --auth-proxy but without --auth-key allows authPairMiddleware to register any client-chosen accessKeyID with an empty ws.s3Secret. gofakes3 then verifies the request’s SigV4 signature against that same empty secret, while Server.auth passes the access key identifier as both the user and authentication value to the proxy without an independent per-identity secret. An unauthenticated network attacker can therefore choose an arbitrary access key, sign with an empty secret, and reach whatever backend the auth-proxy script resolves for that identity. This issue is fixed in version 1.75.1.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-287","CWE-306"],"references":["https://github.com/rclone/rclone/commit/90595f34f27f569be6b27c57fe5ab65057d323bd","https://github.com/rclone/rclone/releases/tag/v1.75.1","https://github.com/rclone/rclone/security/advisories/GHSA-xwwr-4h3p-r22c","https://github.com/rclone/rclone/security/advisories/GHSA-xwwr-4h3p-r22c"],"products":["rclone:rclone"],"source":"nvd","synced_at":"2026-10-19T22:52:53.108888569+00:00"},"epss":{"cve":"CVE-2026-88018","score":0.0051,"percentile":0.43564,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-xwwr-4h3p-r22c","url":"https://osv.dev/vulnerability/GHSA-xwwr-4h3p-r22c","summary":"rclone serve s3: --auth-proxy without --auth-key authenticates nobody - full SigV4 signature bypass","modified":"2026-09-17T17:41:03.623612613Z","packages":[{"ecosystem":"Go","name":"github.com/rclone/rclone","purl":"pkg:golang/github.com/rclone/rclone","ranges":["<1.75.1"],"fixed":["1.75.1"]}]},{"id":"GO-2026-6462","url":"https://osv.dev/vulnerability/GO-2026-6462","summary":"rclone serve s3: --auth-proxy without --auth-key authenticates nobody - full SigV4 signature bypass in github.com/rclone/rclone","modified":"2026-09-17T17:41:03.623612613Z","packages":[{"ecosystem":"Go","name":"github.com/rclone/rclone","purl":"pkg:golang/github.com/rclone/rclone","ranges":["<1.75.1"],"fixed":["1.75.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}