Medium severity · published Aug 25, 2026
CVE-2026-79780
rclone before v1.75.0 Credential Exposure via S3 Redirect
5.3
CVSS
0.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Adjacent
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RC
rclone · rclone
before 1.75.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-79780
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-79780
github.com
https://github.com/rclone/rclone/security/advisories/GHSA-8mxv-9xhp-86h4
www.vulncheck.com
https://www.vulncheck.com/advisories/rclone-before-credential-exposure-via-s3-redirect
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