How severe is CVE-2026-27578?

No CVSS score has been assigned to CVE-2026-27578 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-27578?

CVE-2026-27578 affects the following packages: n8n (npm), n8n (npm), n8n (npm). Ecosystems affected: npm.

How do I fix CVE-2026-27578?

Update n8n to 1.123.22 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-27578 is resolved across your whole dependency graph.

How do I detect CVE-2026-27578 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-2026-27578 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2026-27578?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-27578 can be triaged on real exposure rather than presence alone.

Is CVE-2026-27578 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-27578 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-2026-27578?

CVE-2026-27578 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 8th 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-2026-27578?

CVE-2026-27578 is classified as Cross-site Scripting (XSS) (CWE-79), CWE-80 (CWE-80). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-27578 published, and has it been updated?

CVE-2026-27578 was published on February 25, 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.

CVE-2026-27578: n8n

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs8th percentile — riskier than 8% of all scored CVEsHighest risk

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.

Real-World Exposure

3 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

69Kdownloads / week

Description

n8n is an open source workflow automation platform. Prior to versions 2.10.1, 2.9.3, and 1.123.22, an authenticated user with permission to create or modify workflows could inject arbitrary scripts into pages rendered by the n8n application using different techniques on various nodes (Form Trigger node, Chat Trigger node, Send & Wait node, Webhook Node, and Chat Node). Scripts injected by a malicious workflow execute in the browser of any user who visits the affected page, enabling session hijacking and account takeover. The issues have been fixed in n8n versions 2.10.1 and 1.123.21. Users should upgrade to one of these versions or later to remediate the vulnerability. If upgrading is not immediately possible, administrators should consider the following temporary mitigations. Limit workflow creation and editing permissions to fully trusted users only, and/or disable the Webhook node by adding n8n-nodes-base.webhook to the NODES_EXCLUDE environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`n8n`	all versions	1.123.22`npm install n8n@1.123.22`
📦npm	`n8n`	≥ 2.0.0&&< 2.9.3	2.9.3`npm install n8n@2.9.3`
📦npm	`n8n`	≥ 2.10.0&&< 2.10.1	2.10.1`npm install n8n@2.10.1`

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 1.123.22 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-27578 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 CVE-2026-27578 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2026-27578. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

n8n is an open source workflow automation platform. Prior to versions 2.10.1, 2.9.3, and 1.123.22, an authenticated user with permission to create or modify workflows could inject arbitrary scripts into pages rendered by the n8n application using different techniques on various nodes (Form Trigger node, Chat Trigger node, Send & Wait node, Webhook Node, and Chat Node). Scripts injected by a malicious workflow execute in the browser of any user who visits the affected page, enabling session hijacking and account takeover. The issues have been fixed in n8n versions 2.10.1 and 1.123.21. Users sho

O3 Security · Impact-Aware SCA

Is CVE-2026-27578 in your dependencies?

O3 Security finds CVE-2026-27578 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works

CVE-2026-27578 — n8n