Description
rclone serve s3 versions 1.75.0 before 1.75.2 contain an integer overflow vulnerability in multipart reorder-memory accounting that bypasses the configured buffer limit. Attackers can open two concurrent current-part PUT requests declaring huge lengths to wrap the signed int64 counter and retain out-of-order parts in memory, exhausting the host.
Affected products
rclone: rclone
References3
- github.com/rclone/rclone/security/advisories/GHSA-qjw8-8hmp-c3m6 Vendor Advisory
- github.com/rclone/rclone/security/advisories/GHSA-qjw8-8hmp-c3m6 Vendor Advisory
- www.vulncheck.com/advisories/rclone-serve-s3-1.75.0-before-1.75… Third Party Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 17 · as of 8 November 2026
- CWE
- CWE-190
Could this be exploited in your environment?
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