Uncontrolled Memory Allocation in rclone - #VU147305
Published: September 7, 2026
Vulnerability identifier: #VU147305
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-789
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to memory allocation with excessive size value in the S3 streamed multipart UploadPart handler when processing multipart upload requests with an attacker-controlled declared part length. A remote attacker can send a multipart upload request with an oversized declared part length and withhold the request body to cause a denial of service.
Unauthenticated exploitation applies when anonymous S3 mode is enabled.
Affected software
rclone
Remediation
Install security update from vendor's website.
rclone - update to 1.75.1