rclone serve s3 Path Traversal via dot-dot object keys
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.
Summary
rclone serve s3 before 1.74.4 contains a path traversal vulnerability that allows attackers to read and overwrite root-level files by using dot-dot segments in S3 object keys. Attackers can send requests with object keys like ../root-secret.txt to escape the bucket namespace and access files in the serve root directory.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA rclone (rclone) Fixed in 1.74.4
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
rclone 1.74.4
3 records Highest priority Priority HIGH 1 HIGH, 1 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2026-55260 rclone before 1.74.4 Privilege Escalation via setuid MetadataPriority MEDIUM 44
- TI-2026-55259 rclone before 1.74.4 Security Token Disclosure via HTTPS to HTTP RedirectPriority LOW 39
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Cryostat 4 | Affected | No fix yet: Fix deferred |
| Red Hat Advanced Cluster Management for Kubernetes 2 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-79781
- 2026-10-03 Alias added: GHSA-98fh-ch8q-6529
References
More rclone vulnerabilities
- 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-2026-60064 rclone: RC per-server auth-proxy bypass CVSS 3.1CRITICAL 9.1
- TI-2026-42602 Path traversal in rclone CVSS 3.1HIGH 8.8
- TI-2026-60065 rclone: S3 multipart declared-length memory exhaustion CVSS 3.1HIGH 7.5
Sources
- CVE-2026-79781 · CVE Program
- CVE-2026-79781 · NVD
- FIRST EPSS
- GHSA-98fh-ch8q-6529 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-79781 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences