CVE-2026-21877 Details.
n8n >= 0.123.0 and < 1.121.3 - Remote Code Execution
Atlas does not check this one. Works by exploiting the flaw.
The only reliable test for this one is to try the weakness itself, which can disturb the site. Atlas does not do that, so it does not run this check.
About CVE-2026-21877. What It Means.
n8n versions >= 0.123.0 and < 1.121.3 contain a critical authenticated remote code execution vulnerability via arbitrary file write. An authenticated user can exploit the Git node to overwrite critical files and execute untrusted code on the n8n server, potentially leading to full system compromise. The vulnerability affects both self-hosted and n8n Cloud instances.
Affected Product. What Is Hit.
- Vendor
- n8n-io
- Product
- N8N-IO N8N
References. Where To Read More.
FAQ
Common Questions.
n8n >= 0.123.0 and < 1.121.3 - Remote Code Execution. n8n versions >= 0.123.0 and < 1.121.3 contain a critical authenticated remote code execution vulnerability via arbitrary file write. An authenticated user can exploit the Git node to overwrite critical files and execute untrusted code on the n8n server, potentially leading to full system compromise. The vulnerability affects both self-hosted and n8n Cloud instances.
No. The only reliable test for this one is to try the weakness itself, which can disturb the site. Atlas does not do that, so it does not run this check. The facts about CVE-2026-21877 are on this page, and you can request a demo to see how Brandefense watches your whole external attack surface.
CVE-2026-21877 is not on the CISA Known Exploited Vulnerabilities list at the time of writing, but it is still worth fixing.
Update N8N-IO N8N to the latest version from the vendor, or follow the vendor's advice to switch off the affected feature. Vendor links are listed on this page when they are known.
This page lists the public facts about CVE-2026-21877. Atlas does not run a check for it, so nothing here says whether a particular site is affected.