All Threat Alerts
criticalCVE Alert
CVE-2026-48020

Critical Vulnerability: CVE-2026-48020 โ€” traefik โ€” traefik

Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.48, 3.6.19, and 3.7.3, there is a high severity vulnerability in Traefik's StripPrefix middleware that allows an unauthenticated attacker to bypass route-level authentication and authorization. When a public router matches on a PathPrefix rule and applies the StripPrefix middleware, a request path containing .. or its percent-encoded form %2e%2e can match the public route at routing time and then, after the prefix is stripped and

Friday, June 26, 2026traefikVulnios Threat Intelligence
Share:

Vulnerability Snapshot

CVE-2026-48020 is rated CRITICAL โ€” exploitation is trivial or already observed in the wild and impact is severe. Patch immediately, not on the next maintenance window.

Affected technology: traefik.

Executive Summary

Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.48, 3.6.19, and 3.7.3, there is a high severity vulnerability in Traefik's StripPrefix middleware that allows an unauthenticated attacker to bypass route-level authentication and authorization. When a public router matches on a PathPrefix rule and applies the StripPrefix middleware, a request path containing .. or its percent-encoded form %2e%2e can match the public route at routing time and then, after the prefix is stripped and the path is normalized, resolve to a path served by a separate, authenticated router. As a result, an attacker can reach protected backend paths โ€” such as admin or internal configuration endpoints โ€” without satisfying the authentication middleware attached to the protected router. This vulnerability is fixed in 2.11.48, 3.6.19, and 3.7.3.

Why It Matters

CVE-2026-48020 is rated CRITICAL severity, requiring immediate attention from security teams.

CVSS Base Score: 10/10

EPSS (Exploit Prediction): 0.5% probability of exploitation in the next 30 days.

Affected Technologies

Vendors: traefik

Products: traefik

๐Ÿ›ก๏ธWhat Defenders Should Check

  • Check if you are affected โ€” Review your asset inventory for products listed in CVE-2026-48020.
  • Apply available patches โ€” Visit vendor advisories for the latest security updates.
  • Monitor for exploitation โ€” Check your SIEM/IDS logs for related indicators.
  • Use Vulnios to continuously monitor your exposure to CVE-2026-48020 and similar vulnerabilities.

    References & Sources

    How Vulnios Detects This

    Vulnios scans for this vulnerability using Trivy and Grype for SBOM-based CVE matching and Vulnios CVE feed continuous monitoring against your asset inventory. Run a scan against your environment to see whether you are exposed; findings are linked back to the original CVE record so triage starts with the patch path already known.

    AI Security Advisor

    Powered by Gemini

    Get AI-powered security recommendations tailored to this specific threat โ€” including risk assessment, detection guidance, MITRE ATT&CK mapping, and actionable remediation steps.

    Affected Products

    traefik

    Sources

    Related Threat Alerts

    Frequently Asked Questions

    What is CVE-2026-48020?

    CVE-2026-48020 is a critical-severity vulnerability tracked under the Common Vulnerabilities and Exposures program. Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.48, 3.6.19, and 3.7.3, there is a high severity vulnerability in Traefik's StripPrefix middleware that allows an unauthenticated attac

    Am I affected?

    Check whether your environment runs traefik. If you operate any of those, treat yourself as in scope until you have evidence otherwise. A Vulnios scan will identify the exact assets carrying the affected version.

    How urgent is the response?

    Critical: do not wait for your normal patch cycle. Verify exposure today, apply the vendor patch immediately, and add detection rules for any post-exploit indicators.

    How do I remediate?

    Apply the vendor patch listed in the upstream advisory linked under Sources. If the patch is not yet available, follow the vendor-supplied workaround (often a config flag or feature disable) and add detections for the published exploit pattern in your SIEM. Re-scan after the patch lands to confirm the finding clears.

    Where can I track exploitation activity?

    Watch CISA's Known Exploited Vulnerabilities catalog for CVE-2026-48020. Cross-reference with public exploit databases and your own SIEM/IDS for indicator-of-compromise patterns. Vulnios tracks KEV status automatically and surfaces it on the asset findings view.

    How does Vulnios help with this?

    Vulnios continuously cross-references your asset inventory against the live CVE feed (NVD, vendor advisories, CISA KEV, and curated OSINT). When a new CVE matches your environment, you get a prioritized finding with the severity, KEV status, exploit-prediction (EPSS), and a direct path to the vendor patch. You can start a free scan from the homepage.

    critical

    Protect Your Organization

    Monitor CVEs, scan for vulnerabilities, and get real-time threat alerts โ€” all in one platform.

    Get instant alerts on Telegram

    Join our public channel for real-time critical CVE alerts.

    Follow @vulnios