CVE-2026-27493 (GCVE-0-2026-27493)
Vulnerability from cvelistv5
Published
2026-02-25 22:05
Modified
2026-02-26 20:27
Severity ?
VLAI Severity ?
EPSS score ?
CWE
Summary
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.
References
| URL | Tags | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||
Impacted products
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-27493",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-02-26T20:27:11.761308Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-02-26T20:27:26.036Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "n8n",
"vendor": "n8n-io",
"versions": [
{
"status": "affected",
"version": "\u003c 1.123.22"
},
{
"status": "affected",
"version": "\u003e= 2.0.0, \u003c 2.9.3"
},
{
"status": "affected",
"version": "\u003e= 2.10.0, \u003c 2.10.1"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "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\u0027s 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 \u2014 the character is not rendered in the output, so the result would not match the designer\u0027s 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."
}
],
"metrics": [
{
"cvssV4_0": {
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 9.5,
"baseSeverity": "CRITICAL",
"privilegesRequired": "NONE",
"subAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "HIGH",
"userInteraction": "NONE",
"vectorString": "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",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-94",
"description": "CWE-94: Improper Control of Generation of Code (\u0027Code Injection\u0027)",
"lang": "en",
"type": "CWE"
}
]
},
{
"descriptions": [
{
"cweId": "CWE-95",
"description": "CWE-95: Improper Neutralization of Directives in Dynamically Evaluated Code (\u0027Eval Injection\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-02-25T22:05:00.686Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/n8n-io/n8n/security/advisories/GHSA-75g8-rv7v-32f7",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/n8n-io/n8n/security/advisories/GHSA-75g8-rv7v-32f7"
},
{
"name": "https://github.com/n8n-io/n8n/issues/19",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/n8n-io/n8n/issues/19"
},
{
"name": "https://github.com/n8n-io/n8n/commit/562d867483e871b0f1e31776252e23bd721df75b",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/n8n-io/n8n/commit/562d867483e871b0f1e31776252e23bd721df75b"
},
{
"name": "https://github.com/n8n-io/n8n/releases/tag/n8n@1.123.22",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/n8n-io/n8n/releases/tag/n8n@1.123.22"
},
{
"name": "https://github.com/n8n-io/n8n/releases/tag/n8n@2.10.1",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/n8n-io/n8n/releases/tag/n8n@2.10.1"
},
{
"name": "https://github.com/n8n-io/n8n/releases/tag/n8n@2.9.3",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/n8n-io/n8n/releases/tag/n8n@2.9.3"
}
],
"source": {
"advisory": "GHSA-75g8-rv7v-32f7",
"discovery": "UNKNOWN"
},
"title": "n8n has Unauthenticated Expression Evaluation via Form Node"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-27493",
"datePublished": "2026-02-25T22:05:00.686Z",
"dateReserved": "2026-02-19T19:46:03.542Z",
"dateUpdated": "2026-02-26T20:27:26.036Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-27493\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-02-26T20:27:11.761308Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-02-26T20:27:17.468Z\"}}], \"cna\": {\"title\": \"n8n has Unauthenticated Expression Evaluation via Form Node\", \"source\": {\"advisory\": \"GHSA-75g8-rv7v-32f7\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV4_0\": {\"version\": \"4.0\", \"baseScore\": 9.5, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"CRITICAL\", \"vectorString\": \"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\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"HIGH\", \"vulnIntegrityImpact\": \"HIGH\", \"subAvailabilityImpact\": \"HIGH\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"HIGH\", \"vulnConfidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"n8n-io\", \"product\": \"n8n\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 1.123.22\"}, {\"status\": \"affected\", \"version\": \"\u003e= 2.0.0, \u003c 2.9.3\"}, {\"status\": \"affected\", \"version\": \"\u003e= 2.10.0, \u003c 2.10.1\"}]}], \"references\": [{\"url\": \"https://github.com/n8n-io/n8n/security/advisories/GHSA-75g8-rv7v-32f7\", \"name\": \"https://github.com/n8n-io/n8n/security/advisories/GHSA-75g8-rv7v-32f7\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/n8n-io/n8n/issues/19\", \"name\": \"https://github.com/n8n-io/n8n/issues/19\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/n8n-io/n8n/commit/562d867483e871b0f1e31776252e23bd721df75b\", \"name\": \"https://github.com/n8n-io/n8n/commit/562d867483e871b0f1e31776252e23bd721df75b\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/n8n-io/n8n/releases/tag/n8n@1.123.22\", \"name\": \"https://github.com/n8n-io/n8n/releases/tag/n8n@1.123.22\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/n8n-io/n8n/releases/tag/n8n@2.10.1\", \"name\": \"https://github.com/n8n-io/n8n/releases/tag/n8n@2.10.1\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/n8n-io/n8n/releases/tag/n8n@2.9.3\", \"name\": \"https://github.com/n8n-io/n8n/releases/tag/n8n@2.9.3\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"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\u0027s 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 \\u2014 the character is not rendered in the output, so the result would not match the designer\u0027s 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.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-94\", \"description\": \"CWE-94: Improper Control of Generation of Code (\u0027Code Injection\u0027)\"}]}, {\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-95\", \"description\": \"CWE-95: Improper Neutralization of Directives in Dynamically Evaluated Code (\u0027Eval Injection\u0027)\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-02-25T22:05:00.686Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-27493\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-02-26T20:27:26.036Z\", \"dateReserved\": \"2026-02-19T19:46:03.542Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-02-25T22:05:00.686Z\", \"assignerShortName\": \"GitHub_M\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…