n8n-io n8n up to 2.39.5/2.40.0 SendGrid/Freshservice/ServiceNow escape output

Summaryinfo

A vulnerability, which was classified as problematic, was found in n8n-io n8n up to 2.39.5/2.40.0. This affects an unknown function of the component SendGrid/Freshservice/ServiceNow. The manipulation results in escape output. This vulnerability is identified as CVE-2026-103258. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in n8n-io n8n up to 2.39.5/2.40.0. Affected is some unknown functionality of the component SendGrid/Freshservice/ServiceNow. The manipulation with an unknown input leads to a escape output vulnerability. CWE is classifying the issue as CWE-116. The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved. This is going to have an impact on confidentiality. CVE summarizes:

n8n versions before 2.39.6 and 2.40.0 before 2.40.1 contain an unescaped parameter interpolation vulnerability in SendGrid, Freshservice, and ServiceNow nodes that allows attackers to bypass filters by breaking out of query literals. Attackers can exploit this by binding vulnerable node parameters to untrusted external input to widen single-record lookups into match-all queries, exposing bulk data including contact lists, tickets, and directory entries.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-103258 since 09/30/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available.

Upgrading to version 2.39.6 or 2.40.1 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• n8n-io

Name

• n8n

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27
• 2.28
• 2.29
• 2.30
• 2.31
• 2.32
• 2.33
• 2.34
• 2.35
• 2.36
• 2.37
• 2.38
• 2.39
• 2.39.0
• 2.39.1
• 2.39.2
• 2.39.3
• 2.39.4
• 2.39.5
• 2.40.0

Website

• Product: https://github.com/n8n-io/n8n/

CPE 2.3info

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CPE 2.2info

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