HIGH CVSS 7.5
Published: 2026-04-21

CVE-2026-40938

linuxfoundation tekton_pipelines Security Advisory (CVE-2026-40938)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-40938 impacting linuxfoundation tekton_pipelines. Evaluated with CVSS Base Score of 7.5 (HIGH).

Original NVD Description

Source: NIST NVD
Tekton Pipelines project provides k8s-style resources for declaring CI/CD-style pipelines. Starting in version 1.0.0 and prior to versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1, the git resolver's revision parameter is passed directly as a positional argument to git fetch without any validation that it does not begin with a - character. Because git parses flags from mixed positional arguments, an attacker can inject arbitrary git fetch flags such as --upload-pack=<binary>. Combined with the validateRepoURL function explicitly permitting URLs that begin with / (local filesystem paths), a tenant who can submit ResolutionRequest objects can chain these two behaviors to execute an arbitrary binary on the resolver pod. The tekton-pipelines-resolvers ServiceAccount holds cluster-wide get/list/watch on all Secrets, so code execution on the resolver pod enables full cluster-wide secret exfiltration. Versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1 fix the issue.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Network (AV:N)
Exploitable remotely across internet boundaries
Attack Complexity
High (AC:H)
Depends on race conditions or environment
Privileges Required
Low (PR:L)
Standard user access required
User Interaction
None (UI:N)
Zero human interaction required
Scope
Unchanged (S:U)
Confined to same security context
Confidentiality
High (C:H)
Total information disclosure
Integrity
High (I:H)
Total modification of target system
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product linuxfoundation / tekton_pipelines
Affected Versions *
Weakness Enumeration CWE-88

Security Research Arsenal: Nuclei Detection Template & PoC Exploit Probe

High-Intent Research Tool

Ready-to-use security scanner signatures, active verification probe skeletons, and remediation playbooks for CVE-2026-40938 impacting linuxfoundation tekton_pipelines.

⚡ Nuclei Detection Template (YAML) cve-2026-40938.yaml
id: cve-2026-40938

info:
  name: linuxfoundation tekton_pipelines - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2026-40938 affecting linuxfoundation tekton_pipelines.
    Evaluation: Tekton Pipelines project provides k8s-style resources for declaring CI/CD-style pipelines. Starting in version 1.0.0 and prior to versions 1.0.2, 1.3....
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-40938
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 7.5
    cve-id: CVE-2026-40938
    cwe-id: CWE-88
  tags: cve,cve-2026-40938,linuxfoundation,tekton_pipelines,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "tekton_pipelines"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-40938.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-40938
# Target: linuxfoundation tekton_pipelines | CVSS: 7.5 (HIGH)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-40938 (linuxfoundation tekton_pipelines)...")
    headers = {
        "User-Agent": "CyberVault-Audit-Scanner/2.0",
        "Accept": "*/*"
    }
    try:
        r = requests.get(f"{target_url.rstrip('/')}/", headers=headers, timeout=8, verify=False)
        print(f"[+] Server Response: HTTP {r.status_code} | Server Banner: {r.headers.get('Server', 'Unknown')}")
        if r.status_code < 500:
            print(f"[!] Target reachable. Verify version against linuxfoundation tekton_pipelines scope (*).")
        return True
    except Exception as e:
        print(f"[-] Connection Error: {e}")
        return False

if __name__ == '__main__':
    url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8080"
    verify_vulnerability(url)
🛡️ Quick Patch & Remediation Script (Bash) patch_cve-2026-40938.sh
# Recommended Remediation & Patching Commands for CVE-2026-40938
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install tekton_pipelines 2>/dev/null || \
sudo dnf upgrade tekton_pipelines 2>/dev/null || \
sudo yum update tekton_pipelines

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i tekton_pipelines 2>/dev/null || rpm -qa | grep -i tekton_pipelines

# 3. Docker container & image vulnerability scan:
docker scan $(docker ps -q) 2>/dev/null || echo "Verify upstream base images in Dockerfile."

🛡️ Remediation & Security Action

  • Authoritative Guidance: Follow distribution-specific vendor security notices. Advisory status and package patches vary by distribution release.
  • Verification: Inspect installed binary packages and package manager versions for affected component releases.
  • Upstream Status: Upgrade to verified non-backdoored upstream versions or roll back to known-clean stable releases.
⚠️ Disclaimer: Follow vendor-specific advisories for your operating system. CyberVault does not fabricate unsupported remediation scripts.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2026-40938 in linuxfoundation tekton_pipelines?

Review vendor-specific security notices and update linuxfoundation tekton_pipelines packages to the latest patched release immediately. If immediate upgrading is restricted by change windows, isolate affected network ports and enforce least-privilege access boundaries.

Is there an active exploit or public PoC for CVE-2026-40938?

No weaponized public exploit has been confirmed in public threat streams yet. Continuous surveillance is active across GitHub and security feeds.

What is the CVSS 3.1 severity rating and impact for CVE-2026-40938?

CVE-2026-40938 is classified with a CVSS 3.1 Base Score of 7.5 (HIGH). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
7.5
HIGH SEVERITY
CVE ID CVE-2026-40938
Weakness CWE-88
Vendor linuxfoundation
Product tekton_pipelines
Published 2026-04-21
Vector CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H