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TI-2026-55252 Aliases CVE-2026-79775GHSA-hqq5-m7fp-mqc3

rclone Archive Backend SquashFS Parser Denial of Service

Priority MEDIUM 64CWE-129Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Deferred Red Hat: fix deferred

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-129 and the CVSS impact.

Summary

rclone versions >= v1.72.0 and <= v1.74.4 (fixed in v1.75.0) contain multiple denial-of-service vulnerabilities in the archive backend's SquashFS parser, which relies on the github.com/diskfs/go-diskfs dependency. The parser fails to validate attacker-controlled superblock and metadata values before use. An attacker who can place or modify a SquashFS image in storage exposed through an rclone :archive: remote can craft a malicious image that triggers an integer division-by-zero panic (zero block size), an out-of-bounds slice panic (out-of-range inode metadata offset), or a non-progress CPU loop (truncated metadata stream). Variants 1 and 2 terminate the rclone process and, via 'rclone serve sftp', can crash the entire SFTP server; variant 3 causes sustained CPU consumption. Parsing is lazy, so a victim or remote client must address or descend into the malicious archive object to trigger it.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00371 31st percentileScored 2026-11-07
Fix Deferred Red Hat: fix deferred

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
rclonerclone1.72.0 – 1.74.4—No fix listedCNA
  • rclone Vendorrclone Affected 1.72.0 – 1.74.4 Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:rclone:rclone:*:*:*:*:*:*:*:*——rclone
  • cpe:2.3:a:rclone:rclone:*:*:*:*:*:*:*:* Versions — — ·rclone

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Assisted Installer for Red Hat OpenShift Container Platform 2AffectedNo fix planned: Out of support scope
Cryostat 4AffectedNo fix yet: Fix deferred
Exploit IntelligenceAffectedNo fix planned: Out of support scope
Multicluster Engine for KubernetesAffectedNo fix yet: Fix deferred
Red Hat Advanced Cluster Management for Kubernetes 2AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-79775
  2. 2026-10-03 Alias added: GHSA-hqq5-m7fp-mqc3
  3. 2026-11-01 Affected versions changed · Red Hat

References

Advisory 1

  • 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
See all 43 →

Sources

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