CVE-2026-21877

Published Jan 8, 2026

Last updated 2 months ago

CVSS critical 9.9
API

Overview

Description
n8n is an open source workflow automation platform. In versions 0.121.2 and below, an authenticated attacker may be able to execute malicious code using the n8n service. This could result in full compromise and can impact both self-hosted and n8n Cloud instances. This issue is fixed in version 1.121.3. Administrators can reduce exposure by disabling the Git node and limiting access for untrusted users, but upgrading to the latest version is recommended.
Source
security-advisories@github.com
NVD status
Analyzed
Products
n8n

Risk scores

CVSS 3.1

Type
Secondary
Base score
9.9
Impact score
6
Exploitability score
3.1
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Severity
CRITICAL

Weaknesses

security-advisories@github.com
CWE-94

Social media

Hype score
Not currently trending

  1. csirt_it: La Settimana Cibernetica del 01 febbraio 2026 🔹 aggiornamenti per molteplici prodotti 🔹Ivanti: rilevate due nuove vulnerabilità, di cui una di tipo zero-day ⚠️ #EPSS: 🔹Ivanti: CVE-2025-22467 🔹n8n: CVE-2026-21877 🔗https://t.co/LJ96VJjGgo https://t.

    @Vulcanux_

    2 Feb 2026

    78 Impressions

    0 Retweets

    0 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

  2. La Settimana Cibernetica del 01 febbraio 2026 🔹 aggiornamenti per molteplici prodotti 🔹Ivanti: rilevate due nuove vulnerabilità, di cui una di tipo zero-day ⚠️ #EPSS: 🔹Ivanti: CVE-2025-22467 🔹n8n: CVE-2026-21877 🔗https://t.co/pHK5h3Jjiz https://t.co/wuilz7q

    @csirt_it

    2 Feb 2026

    310 Impressions

    1 Retweet

    3 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

  3. IMPORTANT: Upgrade your self hosted n8n! All supported versions prior to 2.0.0 are affected. CVE-2025-68613 https://t.co/v5KUleCXlR CVE-2025-68668 https://t.co/PW7rPZkWK6 CVE-2026-21858 https://t.co/GK2twlNwnR CVE-2026-21877 https://t.co/DLDO9vYlfa

    @igz4rd

    28 Jan 2026

    47 Impressions

    0 Retweets

    0 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

  4. Sicherheitsdesaster bei Automatisierungsplattform n8n (CVE-2026-21877, CVE-2025-68668, CVE‑2026‑21858) | Borns IT- und Windows-BlogBorns IT- und Windows-Blog https://t.co/JDnfmW6STY

    @ItE2u

    10 Jan 2026

    49 Impressions

    0 Retweets

    0 Likes

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  5. 12 new OPEN, 15 new PRO (12 + 3) ZPHP, itagent RMM, several CVEs (CVE-2025-15356, CVE-2025-15471, CVE-2026-21877) and more. https://t.co/cgfguZ6E8F

    @ET_Labs

    7 Jan 2026

    226 Impressions

    2 Retweets

    2 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

Configurations

Related CVEs

  1. 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 leverage the Merge node's SQL query mode to execute arbitrary code and write arbitrary files on the n8n server. The issues have been fixed in n8n versions 2.10.1, 2.9.3, and 1.123.22. Users should upgrade to one of these versions or later to remediate all known vulnerabilities. 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 Merge node by adding `n8n-nodes-base.merge` to the `NODES_EXCLUDE` environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.•CVE-2026-27497
  2. n8n is an open source workflow automation platform. Prior to versions 2.2.0 and 1.123.8, an authenticated user with permission to create or modify workflows could chain the Read/Write Files from Disk node with git operations to achieve remote code execution. By writing to specific configuration files and then triggering a git operation, the attacker could execute arbitrary shell commands on the n8n host. The issue has been fixed in n8n versions 2.2.0 and 1.123.8. 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 Read/Write Files from Disk node by adding `n8n-nodes-base.readWriteFile` to the `NODES_EXCLUDE` environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.•CVE-2026-27498
  3. 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.•CVE-2026-27578
  4. n8n is an open source workflow automation platform. Prior to versions 2.10.1, 2.9.3, and 1.123.22, additional exploits in the expression evaluation of n8n have been identified and patched following CVE-2025-68613. An authenticated user with permission to create or modify workflows could abuse crafted expressions in workflow parameters to trigger unintended system command execution on the host running n8n. The issues have been fixed in n8n versions 2.10.1, 2.9.3, and 1.123.22. Users should upgrade to one of these versions or later to remediate all known vulnerabilities. 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 deploy n8n in a hardened environment with restricted operating system privileges and network access to reduce the impact of potential exploitation. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.•CVE-2026-27577
  5. n8n is an open source workflow automation platform. Prior to versions 2.10.1, 2.9.3, and 1.123.22, a second-order expression injection vulnerability existed in n8n's Form nodes that could allow an unauthenticated attacker to inject and evaluate arbitrary n8n expressions by submitting crafted form data. When chained with an expression sandbox escape, this could escalate to remote code execution on the n8n host. The vulnerability requires a specific workflow configuration to be exploitable. First, a form node with a field interpolating a value provided by an unauthenticated user, e.g. a form submitted value. Second, the field value must begin with an `=` character, which caused n8n to treat it as an expression and triggered a double-evaluation of the field content. There is no practical reason for a workflow designer to prefix a field with `=` intentionally — the character is not rendered in the output, so the result would not match the designer's expectations. If added accidentally, it would be noticeable and very unlikely to persist. An unauthenticated attacker would need to either know about this specific circumstance on a target instance or discover a matching form by chance. Even when the preconditions are met, the expression injection alone is limited to data accessible within the n8n expression context. Escalation to remote code execution requires chaining with a separate sandbox escape vulnerability. The issue has been fixed in n8n versions 2.10.1, 2.9.3, and 1.123.22. 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. Review usage of form nodes manually for above mentioned preconditions, disable the Form node by adding `n8n-nodes-base.form` to the `NODES_EXCLUDE` environment variable, and/or disable the Form Trigger node by adding `n8n-nodes-base.formTrigger` to the `NODES_EXCLUDE` environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.•CVE-2026-27493

References

Sources include official advisories and independent security research.