Vulnerability · Published Oct 25, 2026 · Assigned by VulnCheck

CVE-2026-116187Rclone v1.68.0 before v1.75.2 Authorization Bypass in serve s3 Multipart Uploads

Medium 5.0

In plain English

A medium-severity authorization bypass via user-controlled key in rclone from rclone. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.0Medium

Exploit odds (30 days)0.1%top 96.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Rclone from v1.68.0 before v1.75.2 contains an authorization bypass vulnerability in serve s3 --auth-proxy that allows authenticated tenants to manipulate other tenants' multipart uploads by referencing their upload IDs. Attackers who learn a victim's bucket, object, and upload ID can inject parts, complete, or abort in-flight uploads and view upload and object metadata across tenants.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Alpine:v3.24	rclone	1.75.2-r0	ALPINE-CVE-2026-116187
Ubuntu:26.10	rclone	no fix listed	UBUNTU-CVE-2026-116187

Affected products (as reported)

Vendor	Product	Versions
rclone	rclone	1.68.0 – before 1.75.2

Weakness: CWE-639 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L

References

GitHub Security Advisory (GHSA-35g6-9fjv-rmx5) vendor-advisory
VulnCheck Advisory: Rclone v1.68.0 before v1.75.2 Authorization Bypass in serve s3 Multipart Uploads third-party-advisory