How severe is CVE-2026-21858?

CVE-2026-21858 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-21858 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 72% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-21858?

CVE-2026-21858 affects N8n. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-21858?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-21858 have an EU (EUVD) identifier?

Yes. CVE-2026-21858 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-1187.

When was CVE-2026-21858 published?

CVE-2026-21858 was published on 2026-01-08 and last updated on 2026-06-17.

CVE-2026-21858

CVE-2026-21858 is a critical-severity vulnerability in N8n with a CVSS 3.x base score of 10.0. Its EPSS exploit-prediction score of 72% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 3.x base score 10.0)
EPSS exploit prediction: 72% (99th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-1187
Weakness: CWE-20
Affected product: N8n
Published: 2026-01-08
Last modified: 2026-06-17

Description

n8n is an open source workflow automation platform. Versions starting with 1.65.0 and below 1.121.0 enable an attacker to access files on the underlying server through execution of certain form-based workflows. A vulnerable workflow could grant access to an unauthenticated remote attacker, resulting in exposure of sensitive information stored on the system and may enable further compromise depending on deployment configuration and workflow usage. This issue is fixed in version 1.121.0.

Frequently asked questions

What is CVE-2026-21858?: n8n is an open source workflow automation platform. Versions starting with 1.65.0 and below 1.121.0 enable an attacker to access files on the underlying server through execution of certain form-based workflows. A vulnerable workflow could grant access to an unauthenticated remote attacker, resulting in exposure of sensitive information stored on the system and may enable further compromise depending on deployment configuration and workflow usage. This issue is fixed in version 1.121.0.
How severe is CVE-2026-21858?: CVE-2026-21858 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-21858 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 72% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-21858?: CVE-2026-21858 affects N8n. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-21858?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-21858 have an EU (EUVD) identifier?: Yes. CVE-2026-21858 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-1187.
When was CVE-2026-21858 published?: CVE-2026-21858 was published on 2026-01-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:n8n:n8n:*:*:*:*:*:node.js:*:*

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