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TI-2026-60043 Aliases CVE-2026-88017GHSA-c476-6w5q-jw77

rclone: FTP cross-session auth-proxy backend confusion

Priority LOW 34CWE-488Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

rclone is a command-line program to sync files and directories to and from different cloud storage providers. From 1.64.0 until 1.75.1, the FTP auth-proxy driver in cmd/serve/ftp/ftp.go stores one obscured password per username in the server-wide userPass map[string]string instead of binding the credential or VFS to the authenticated session. If two accepted credentials use the same username but resolve to different proxy backends, a later CheckPasswd login overwrites userPass[user], and subsequent getVFS operations on the first session are reauthorized with the later password. The first session can then read, create, overwrite, rename, or delete objects using the second credential’s backend authority. Exploitation requires the later same-username login to occur while the first session remains open. This issue is fixed in version 1.75.1.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00234 14th percentileScored 2026-11-07
Fix Fixed rclone (rclone): 1.75.1github.com/rclone/rclone (Go): 1.75.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
rclonerclone1.64.0 to before 1.75.11.75.1Patch availableCNA
—github.com/rclone/rclone (Go)1.64.0 to before 1.75.11.75.1Patch availableGHSA-c476-6w5q-jw77
  • rclone Vendorrclone Affected 1.64.0 to before 1.75.1 Fixed in 1.75.1 Patch available CNA
  • github.com/rclone/rclone (Go) Vendor— Affected 1.64.0 to before 1.75.1 Fixed in 1.75.1 Patch available GHSA-c476-6w5q-jw77

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:rclone:rclone:*:*:*:*:*:*:*:*1.64.0 to before 1.75.1Vulnerablerclone
  • cpe:2.3:a:rclone:rclone:*:*:*:*:*:*:*:* Versions 1.64.0 to before 1.75.1 Vulnerable ·rclone

Remediation

  • Fix · CNA rclone (rclone) Fixed in 1.75.1
  • Fix · GHSA-c476-6w5q-jw77 github.com/rclone/rclone (Go) Fixed in 1.75.1 Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-88017
  2. 2026-10-03 Alias added: GHSA-c476-6w5q-jw77

References

Patch 1

Advisory 2

Other 2

  • TI-2026-60044 rclone serve s3: --auth-proxy without --auth-key authenticates nobody - full SigV4 signature bypass CVSS 3.1CRITICAL 9.8
  • TI-2026-29802 RClone: Unauthenticated operations/fsinfo allows attacker-controlled backend instantiation and local command execution CVSS 4.0CRITICAL 9.2
  • TI-2026-29799 Rclone: Unauthenticated options/set allows runtime auth bypass, leading to sensitive operations and command execution CVSS 4.0CRITICAL 9.2
  • TI-2026-42602 Path traversal in rclone CVSS 3.1HIGH 8.8
  • TI-2026-39407 rclone: Unvalidated symlink target in local `--links` — arbitrary file write from an untrusted remote CVSS 3.1HIGH 8.8
  • TI-2026-80211 Authentication bypass in rclone serve webdav via OPTIONS requests CVSS 4.0MEDIUM 6.9
See all 23 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences