Description
Rclone before v1.75.2 contains a credential exposure vulnerability in the b2 backend that leaks the live account Authorization token and SSE-C keys on HTTP redirects from --b2-download-url hosts. Attackers can observe a same-host HTTPS-to-HTTP downgrade redirect to capture the cleartext B2 token, or receive cross-host redirects disclosing SSE-C customer encryption keys.
Affected products
rclone: rclone
References2
- github.com/rclone/rclone/security/advisories/GHSA-gpw7-77cq-9f72 Vendor Advisory
- www.vulncheck.com/advisories/rclone-before-1.75.2-b2-credential… Third Party Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 4.0
-
6.0
MEDIUM
Score source: CNA
CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/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: 0 · as of 8 November 2026
- CWE
- CWE-319
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.