Skip to main content

n8n CVE-2026-77082

| EUVDEUVD-2026-63270 MEDIUM
Inefficient Regular Expression Complexity (ReDoS) (CWE-1333)
2026-08-20 VulnCheck GHSA-jxf5-f3hg-vxvj
Denial Of Service N8n
5.3
CVSS 4.0 · Vendor: VulnCheck
Share

Severity by source

Vendor (VulnCheck) PRIMARY
5.3 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
vuln.today AI
4.3 MEDIUM

Low-privileged authentication required to author workflows; availability impact is partial worker blocking, not full system denial; no scope change beyond the affected worker.

3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Primary rating from Vendor (VulnCheck).

CVSS VectorVendor: VulnCheck

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
X

Lifecycle Timeline

2
Patch available
Aug 20, 2026 - 12:16 EUVD
Analysis Generated
Aug 20, 2026 - 12:13 vuln.today

DescriptionCVE.org

n8n before 1.123.69, 2.x before 2.33.4, and 2.34.x before 2.34.1 contains a regular expression denial of service (ReDoS) vulnerability in the Filter and Switch nodes, which compile user-supplied regex patterns with new RegExp() and execute them synchronously on the worker thread without complexity validation or execution timeout. A crafted regex pattern can block the worker for an extended period per data item processed, delaying other workflow executions on the same worker.

AnalysisAI

ReDoS in n8n's Filter and Switch nodes allows an authenticated workflow author to monopolize a worker thread indefinitely by supplying a catastrophic backtracking regex compiled via new RegExp() without complexity validation or execution timeout. Affected are n8n versions before 1.123.69, 2.x before 2.33.4, and 2.34.x before 2.34.1; per-item execution amplifies the impact proportionally to dataset size, stalling all concurrent workflows on the same worker. …

Unlock full vulnerability intelligence

  • Risk assessment & exploitation conditions
  • Attack chain visualization
  • Remediation with exact patch versions
  • Threat intelligence from 22 sources
  • Personal watchlist & email alerts
Continue with Google Continue with GitHub

Free forever · No credit card required

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata

Access
Obtain low-privileged n8n account
Delivery
Create Filter or Switch node with catastrophic backtracking regex
Exploit
Execute workflow against large non-matching dataset
Execution
Block worker thread synchronously
Impact
Delay all co-located workflow executions
Sign in to reveal

Vulnerability AssessmentAI

Exploitation Exploitation requires an authenticated n8n user account with privileges to create or modify workflows - this is a standard user capability in n8n, not limited to administrators. … Additional conditions and limiting factors are described in the full assessment.
Risk Assessment The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N) places this as a moderate-severity availability issue requiring low-privileged authenticated access with no additional complexity. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in.
Exploit Scenario An authenticated n8n user with workflow editing access creates a Filter node containing a catastrophic backtracking regex such as `^(a+)+$` and triggers the workflow against a dataset of non-matching strings. Each item causes the synchronous regex evaluation on the worker thread to enter exponential backtracking, monopolizing the worker for seconds or minutes per item and stalling all other workflow executions scheduled on that worker. …
Remediation Upgrade n8n to 1.123.69 or later (1.x branch), 2.33.4 or later (2.x branch), or 2.34.1 or later (2.34.x branch) per the vendor advisory at https://github.com/n8n-io/n8n/security/advisories/GHSA-q3fv-295f-qfpf. … Detailed patch versions, workarounds, and compensating controls in full report.
Sign in to read full assessment

Threat intelligence, references, and detailed analysis are available after sign-in.

More in N8n

View all
CVE-2026-21877 CRITICAL POC
9.9 Jan 08

n8n workflow automation (through 1.121.2) allows authenticated users to execute arbitrary code via the n8n service, with
CVE-2026-21858 CRITICAL POC
10.0 Jan 08

n8n workflow automation (1.65.0 to 1.121.0) allows unauthenticated file access through form-based workflows. A critical

CVE-2026-1470 CRITICAL POC
9.9 Jan 27

n8n has a fifth critical RCE vulnerability (CVSS 9.9) in the Expression evaluator, enabling code execution through craft
CVE-2026-33660 CRITICAL POC
9.4 Mar 25

An authenticated user with workflow creation or modification privileges in n8n workflow automation platform can exploit

CVE-2026-33665 HIGH POC
8.8 Mar 25

Authenticated n8n users can hijack administrator accounts when LDAP authentication is enabled by manipulating their LDAP
CVE-2023-27563 HIGH POC
8.8 May 10

The n8n package 0.218.0 for Node.js allows Escalation of Privileges. Rated high severity (CVSS 8.8), this vulnerability

CVE-2026-0863 HIGH POC
8.5 Jan 18

Authenticated users can exploit string formatting and exception handling in n8n's Python task executor to escape sandbox
CVE-2023-27564 HIGH POC
7.5 May 10

The n8n package 0.218.0 for Node.js allows Information Disclosure. Rated high severity (CVSS 7.5), this vulnerability is
CVE-2023-27562 MEDIUM POC
6.5 May 10

The n8n package 0.218.0 for Node.js allows Directory Traversal. Rated medium severity (CVSS 6.5), this vulnerability is

CVE-2026-33724 MEDIUM POC
6.3 Mar 25

n8n versions prior to 2.5.0 contain a critical SSH host key verification bypass in the Source Control feature that allow
CVE-2026-33720 MEDIUM POC
6.3 Mar 25

This vulnerability in n8n (an open-source workflow automation platform) is an authentication bypass in the OAuth callbac
CVE-2026-27495 CRITICAL
9.9 Feb 25

Code injection in n8n workflow automation before 2.10.1/2.9.3/1.123.22 allows authenticated users to execute arbitrary c

Same weakness CWE-1333 – Inefficient Regular Expression Complexity (ReDoS)

View all
CVE-2023-29486 CRITICAL POC
9.8
CVE-2023-29487 CRITICAL POC
9.1
CVE-2026-48801 HIGH POC
8.7
CVE-2024-58340 HIGH POC
8.7
CVE-2026-0621 HIGH POC
8.7
CVE-2024-21490 HIGH POC
7.5
CVE-2022-42969 HIGH POC
7.5
CVE-2015-8315 HIGH POC
7.5

Same technique Denial Of Service

View all
CVE-2015-5119 CRITICAL POC
9.8
CVE-2011-2462 CRITICAL POC
9.8
CVE-2011-0611 HIGH POC
8.8
CVE-2012-1889 HIGH POC
8.8
CVE-2012-0507 CRITICAL POC
9.8
CVE-2014-1761 HIGH POC
7.8
CVE-2015-5122 CRITICAL POC
9.8
CVE-2011-0609 HIGH POC
7.8

Share

CVE-2026-77082 vulnerability details – vuln.today
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy