CVE-2026-79780: rclone before v1.75.0 Credential Exposure via S3 Redirect

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-25 · updated 2026-09-10
Weakness: CWE-200

Description

rclone before v1.75.0 fails to sanitize IBM IAM bearer tokens and SSE-C encryption keys during S3 redirect callbacks, allowing credentials to be preserved across scheme or host changes. Attackers observing network traffic from a trusted endpoint can capture reusable IBM IAM tokens on same-host HTTPS-to-HTTP downgrades or SSE-C keys on cross-origin redirects to access protected S3 objects.

Affected products

rclone: before 1.75.0 — fixed in 1.75.0

How to fix

Upgrade to a fixed version: rclone 1.75.0. Check the vendor advisory for mitigations.

References

https://github.com/rclone/rclone/security/advisories/GHSA-8mxv-9xhp-86h4
https://www.vulncheck.com/advisories/rclone-before-credential-exposure-via-s3-redirect
https://github.com/rclone/rclone/security/advisories/GHSA-8mxv-9xhp-86h4

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