CVE-2026-27493Network attack vector

Unauthenticated expression evaluation via double evaluation

Published Feb 25, 2026 · Updated Feb 25, 2026

Expression injection in affected n8n Form nodes allows remote attackers to evaluate crafted form data in the expression context. A downstream Form node treats an interpolated, attacker-controlled value beginning with = as a fresh expression and evaluates the content twice. Exposure requires an unauthenticated form feeding such a prefixed field; host code execution additionally requires a separate sandbox escape.

CVSS severity9.5
Critical
EPSS probability1.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Expression injection in affected n8n Form nodes allows remote attackers to evaluate crafted form data in the expression context. A downstream Form node treats an interpolated, attacker-controlled value beginning with = as a fresh expression and evaluates the content twice. Exposure requires an unauthenticated form feeding such a prefixed field; host code execution additionally requires a separate sandbox escape.

The record

CVE
CVE-2026-27493
Published
Feb 25, 2026
Updated
Feb 25, 2026
Vendor
n8n
Product
n8n
Classifications
CWE-95, CWE-94, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.123.22
  2. Affected versionversion=>= 2.0.0, < 2.9.3
  3. Affected versionversion=>= 2.10.0, < 2.10.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

n8n · n8nversion=< 1.123.22; version=>= 2.0.0, < 2.9.3; version=>= 2.10.0, < 2.10.1

Published CVSS scores

9.5GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
9.0NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-95Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')
CWE-94Improper Control of Generation of Code ('Code Injection')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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