CVE-2026-59259: n8n before versions 1.123.61, 2.27.4, and 2.28.1 contains a permission bypass vulnerability in external secrets handling caused by a mismatch between the static validation check an

mediumCVSS 6.5CVE-2026-59259

n8n before versions 1.123.61, 2.27.4, and 2.28.1 contains a permission bypass vulnerability in external secrets handling caused by a mismatch between the static validation check and the runtime expression engine. An authenticated user with credential create or update permissions but without the externalSecret:list scope can embed external secret references into credentials in forms the static validation does not detect; these references resolve at workflow execution time, exposing secret values the user is not authorized to access. This issue only affects instances where an external secrets provider is configured and Advanced Permissions are in use.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 6.5
Published: 2026-07-15
Last updated: 2026-07-16
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-59259

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-592590.32% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 24% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-59259	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

mediumGHSA-jp7m-xcgx-57qm: n8n: External Secrets Permission Bypass via Expression Parser Mismatchghsa

Recent advisories for n8n

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

high[NEW] [high] n8n: Multiple vulnerabilitiescert-bund · 2026-07-23
mediumGHSA-652q-gvq3-74qv: n8n: Snowflake Node executeQuery Operation Allows SQL Injection via Unparameterized Expre…ghsa · 2026-07-22
mediumGHSA-jqwr-vx3p-r266: n8n: PostgresTrigger Node SQL Injection Allows Authenticated Users to Execute Arbitrary S…ghsa · 2026-07-22
mediumGHSA-9cmh-xcqm-5hqr: n8n: Cross-Tenant Module-Cache Poisoning in the JS Task Runnerghsa · 2026-07-22
mediumGHSA-89gh-3pgc-v5h2: n8n: Custom Header Credential Values Leaked in Plaintext into LLM Node Execution Dataghsa · 2026-07-22
mediumGHSA-33q9-f52j-gc75: n8n: Unauthenticated Endpoint Allows Cancellation of Any User's Active Test Webhookghsa · 2026-07-22