Cyber Resilience

CVE-2026-41176

Access Control in Rclone 1.45 – 1.73.5

Public PoCAccess Control
Published
23 April 2026
Modified
15 July 2026
Patch / advisory
CVSS Score v4 9.2
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.33 98th percentile
Risk Priority 62 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-41176 is a critical-severity Missing Authentication for Critical Function (CWE-306) vulnerability in Rclone Rclone. Its CVSS base score is 9.2 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception by PATH Environment Variable (T1574.007); ranked in the top 2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-14 (Permitted Actions Without Identification or Authentication) and AC-3 (Access Enforcement) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

Rclone, a command-line program used to synchronize files with cloud storage providers, contains an authentication bypass vulnerability in its remote control (RC) interface. The `options/set` endpoint is registered without the `AuthRequired: true` flag and can alter global runtime settings, including the RC configuration block itself. The flaw affects versions 1.45.0 through 1.73.4 and is tracked as CWE-306.

An unauthenticated network attacker who can reach an RC server started without global HTTP authentication can invoke `options/set` to set `rc.NoAuth=true`. This change disables authorization checks on other RC methods that were intended to require authentication, granting the attacker access to administrative operations such as configuration changes and control functions.

The official advisory GHSA-25qr-6mpr-f7qx and the accompanying patch in version 1.73.5 address the issue by ensuring the `options/set` endpoint cannot be used to override authentication settings without prior authorization. The current and peak EPSS scores both stand at 0.2632, indicating no material increase in observed exploitation interest after disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Rclone is a command-line program to sync files and directories to and from different cloud storage providers. The RC endpoint `options/set` is exposed without `AuthRequired: true`, but it can mutate global runtime configuration, including the RC option block itself. Starting…

more

in version 1.45.0 and prior to version 1.73.5, an unauthenticated attacker can set `rc.NoAuth=true`, which disables the authorization gate for many RC methods registered with `AuthRequired: true` on reachable RC servers that are started without global HTTP authentication. This can lead to unauthorized access to sensitive administrative functionality, including configuration and operational RC methods. Version 1.73.5 patches the issue.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1574.007 Path Interception by PATH Environment Variable Stealth
Adversaries may execute their own malicious payloads by hijacking environment variables used to load libraries.
T1547.004 Winlogon Helper DLL Persistence
Adversaries may abuse features of Winlogon to execute DLLs and/or executables when a user logs in.
T1547.014 Active Setup Persistence
Adversaries may achieve persistence by adding a Registry key to the Active Setup of the local machine.
T1574.006 Dynamic Linker Hijacking Stealth
Adversaries may execute their own malicious payloads by hijacking environment variables the dynamic linker uses to load shared libraries.
T1647 Plist File Modification Defense Impairment
Adversaries may modify property list files (plist files) to enable other malicious activity, while also potentially evading and bypassing system defenses.
T1037 Boot or Logon Initialization Scripts Persistence
Adversaries may use scripts automatically executed at boot or logon initialization to establish persistence.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-88018Same product: Rclone Rclone
CVE-2026-49980Same product: Rclone Rclone
CVE-2026-41179Same product: Rclone Rclone
CVE-2026-59732Same product: Rclone Rclone
CVE-2026-59733Same product: Rclone Rclone
CVE-2026-54572Same product: Rclone Rclone
CVE-2026-88017Same product: Rclone Rclone
CVE-2026-88016Same product: Rclone Rclone
CVE-2026-45087Shared CWE-15, CWE-306
CVE-2024-39280Shared CWE-15

Affected Assets

rclone
rclone
1.45 — 1.73.5

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 10 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.2.3
  • V6.4.4
  • V10.4.16
  • V12.1.3

Mitigating Controls (NIST 800-53 r5) AI

Enforces approved authorizations for logical access to configuration resources so external parties cannot alter them.

Enforces documented access restrictions on all changes to system configuration, directly blocking unauthorized external control of settings.

Directly mandates unique identification and authentication of users before access to functions requiring identity.

Extends the same authentication requirement to non-organizational users accessing critical functionality.

Requires authentication of services before they can invoke or expose critical functions.

Explicitly identifies and limits actions permitted without authentication, preventing critical functions from being exposed.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

ID.RA-07 partial match
prevents

Formal change and exception management catches externally driven configuration alterations.

PR.AA-01 partial match
prevents

Managing identities and credentials is a prerequisite for authentication but does not itself enforce it on critical functions.

PR.AA-03 partial match
prevents

Directly requires authentication of users/services/hardware, which eliminates missing authentication for critical functions.

PR.AA-05 partial match
prevents

Defining and enforcing authorizations assumes prior authentication and therefore only partially mitigates the absence of authentication.

PR.IR-01 partial match
prevents

Protecting networks from unauthorized access can be undermined by missing authentication but does not address the root authentication gap.

PR.PS-01 partial match
prevents

Hardened configuration baselines and change controls directly limit external manipulation of settings.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Access control policies underpin the technical restrictions on configuration changes.

prevents

Access rights assignment determines who may change system settings.

mitigates

Documented operating procedures define how configuration changes must be performed.

prevents

Mandating authentication requirements for critical functions at the requirements-gathering stage ensures that essential operations are not left unprotected by missing login or verification mechanisms.

prevents

Use of privileged utility programs is controlled to prevent misuse of configuration tools.

mitigates

Restricting software installation limits unauthorized changes to configuration.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248585 OL 8 must require reauthentication when using the "sudo" command. prevents CWE-306
  • V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-306
RHEL 7 (2 rules)
  • V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-306
  • V-237635 The Red Hat Enterprise Linux operating system must require re-authentication when using the "sudo" command. prevents CWE-306
RHEL 8 (2 rules)
  • V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-306
  • V-237643 RHEL 8 must require re-authentication when using the "sudo" command. prevents CWE-306

References