GHSA-2m8m-jhrm-w6j2 is a high-severity (CVSS 8) OS Command Injection vulnerability in github.com/rclone/rclone. A fix is available for github.com/rclone/rclone — see the affected versions and patch details below.
rclone: PowerShell Smart-Quote Filename Injection Enables SFTP Server-Side Command Execution
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for GHSA-2m8m-jhrm-w6j2.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-2m8m-jhrm-w6j2 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/rclone/rcloneReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
1. Summary
rclone interpolates remote SFTP paths into PowerShell hash commands. Its quoting helper escapes only ASCII apostrophe, although PowerShell accepts four Unicode smart quotes as single-quote delimiters. An attacker-controlled filename can therefore terminate the intended path literal and append PowerShell statements executed as the victim's SSH account.
2. Affected Assets & Attack Surface
- Audited commit:
a0c09f1381ae93e2a9a33c529d170186c61ad058 - Backend:
backend/sftp - Relevant code:
backend/sftp/sftp.go:1802-1812— PowerShell hash commandsbackend/sftp/sftp.go:1663-1699—Fs.runbackend/sftp/sftp.go:1988-2067—Object.Hashbackend/sftp/sftp.go:2071-2090—quoteOrEscapeShellPath
- Exposed input: remote filename controlled by an SFTP collaborator, upstream storage source, or other party able to create or rename files.
- Required execution context: PowerShell as the SSH command shell, SSH exec enabled, and server-side hashing invoked.
3. Technical Root Cause Analysis
For PowerShell, quoteOrEscapeShellPath wraps a path in ASCII apostrophes and doubles only U+0027:
return "'" + strings.ReplaceAll(shellPath, "'", "''") + "'", nil
Windows PowerShell also treats U+2018, U+2019, U+201A, and U+201B as single-quote delimiters. Those characters pass through the rclone encoder and can close the quoted path. The completed string is sent as shell source through an SSH exec request.
The security boundary fails because shell syntax is constructed by string concatenation rather than passing data through a non-code channel.
4. Proof-of-Concept & Evidence
- Each of the four Unicode smart quotes was passed through the production quoting function and used to terminate the path literal.
- A harmless injected
Set-Contentstatement created a marker file. - The stronger test invoked the exact production
Object.Hashpath and MD5 PowerShell command against a fake SSH session backed by local PowerShell. - A valid prefix file allowed
Get-FileHashto complete; the appended statement then executed. - The filename used only characters permitted by Windows filesystems and did not depend on slash, colon, pipe, or ASCII apostrophe.
- The focused test passed normally and under Go's race detector.
Reproduction outline:
- Configure an SFTP remote whose command shell is PowerShell.
- Enable or autodetect the PowerShell hash command.
- Place a file whose name contains a smart quote followed by a harmless marker-writing statement and PowerShell comment syntax.
- Trigger an rclone operation that calculates the remote hash.
- Observe the marker created with the SSH account's permissions.
5. Impact Assessment
Successful exploitation provides arbitrary command execution as the victim's SSH account. This can permit file theft, modification, deletion, credential access, persistence, and lateral movement allowed by that account.
The attacker needs filename-control capability but does not need the victim's SSH credentials or an interactive shell. The rclone user's hash operation supplies the execution step.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/rclone/rclone | all versions | 1.75.0go get github.com/rclone/rclone@v1.75.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/rclone/rclone, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/rclone/rclone to 1.75.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2m8m-jhrm-w6j2 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-2m8m-jhrm-w6j2 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-2m8m-jhrm-w6j2. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-2m8m-jhrm-w6j2 in your dependencies?
O3 Security finds GHSA-2m8m-jhrm-w6j2 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.