How severe is CVE-2026-58661?

No CVSS score has been assigned to CVE-2026-58661 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-58661?

CVE-2026-58661 affects the following packages: n8n (npm), n8n (npm). Ecosystems affected: npm.

How do I fix CVE-2026-58661?

Update n8n to 2.28.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-58661 is resolved across your whole dependency graph.

How do I detect CVE-2026-58661 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for n8n, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-58661 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2026-58661 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-58661 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-58661?

CVE-2026-58661 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 31th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-58661?

CVE-2026-58661 is classified as CWE-770 (CWE-770). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-58661 published, and has it been updated?

CVE-2026-58661 was published on July 10, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

CVE-2026-58661 — n8n

CVE-2026-58661 is a CWE-770 vulnerability in n8n. A fix is available for n8n — see the affected versions and patch details below.

n8n - Disk Space Exhaustion via Data-Table File Upload Endpoint

Also known asGHSA-w867-jm58-p9pv

Published

Jul 10, 2026

Updated

Aug 12, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Oct 11, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-58661.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs31th percentile — riskier than 31% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

2 pkgs affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

37other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

n8nnpm

110Kdownloads / week

Description

Impact

An authenticated user can repeatedly upload files to the data-table upload endpoint, bypassing the per-request quota check, which does not account for files already written to the shared temporary directory. This causes temporary files to accumulate on disk until the periodic cleanup runs, potentially exhausting available disk space on the host.

Patches

Users should upgrade to the patched version once available to remediate the vulnerability.

Workarounds

If upgrading is not immediately possible, administrators should consider the following temporary mitigations:

Restrict n8n instance access to fully trusted users only.
Set uploadMaxFileSize to a low value to limit individual upload size.
Monitor and alert on disk usage in the n8n temporary upload directory.

These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`n8n`	≥ 2.0.0&&< 2.28.0	2.28.0`npm install n8n@2.28.0`
📦npm	`n8n`	all versions	1.123.58`npm install n8n@1.123.58`

Affected Products

1 product · 4 configurations

Application

n8nn8n

≥ 2.0.0 && < 2.28.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for n8n, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update n8n to 2.28.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-58661 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

## Impact An authenticated user can repeatedly upload files to the data-table upload endpoint, bypassing the per-request quota check, which does not account for files already written to the shared temporary directory. This causes temporary files to accumulate on disk until the periodic cleanup runs, potentially exhausting available disk space on the host. ## Patches Users should upgrade to the patched version once available to remediate the vulnerability. ## Workarounds If upgrading is not immediately possible, administrators should consider the following temporary mitigations: - Restrict n8

O3 Security · Impact-Aware SCA

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CVE-2026-58661 — n8n

Exploitation Status

No confirmed exploitation observed yet

EPSS Exploitation Probability

Real-World Exposure

Description

Impact

Patches

Workarounds

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2026-58661 in your dependencies?