CVE-2026-86248

Description

CLIENT_CERT authentication does not fail as expected for some scenarios when soft fail is disabled vulnerability in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M14 through 11.0.25, from 10.1.22 through 10.1.59, from 9.0.92 through 9.0.121. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

Overview

State: PUBLISHED
Assigner (CNA): apache
CVSS severity: —
CVSS score: —
CVSS vector: —
Effective score: 9.8 / 10 CRITICAL source: NVD
CWE(s): —
Reserved: 2026-09-06
Published: 2026-09-23 11:29 UTC
Last updated: 2026-09-23 16:14 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/86xxx/CVE-2026-86248.json

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-23 12:17:08 UTC
NVD last modified: 2026-09-23 17:58:26 UTC
NVD CVSS v3.1: 9.8 / 10 CRITICAL source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploitability subscore: 3.9 / 10
Impact subscore: 5.9 / 10

NVD-assigned CWE(s): CWE-287 (differs from the CNA list above)

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-85234
Assigner: apache
Published: Sep 23, 2026, 11:29:35 AM
Updated: Sep 23, 2026, 4:14:59 PM
EUVD base score (CVSS 3.1): 9.8 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EUVD-reported EPSS: 0.0000
Vendors: Apache Software Foundation
Products: Apache Tomcat (9.0.92 ≤9.0.121)

Apache Tomcat (11.0.0-M14 ≤11.0.25)

Apache Tomcat (10.1.22 ≤10.1.59)
Aliases: GHSA-c47j-g3rg-hrfq

ENISA description: CLIENT_CERT authentication does not fail as expected for some scenarios when soft fail is disabled vulnerability in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M14 through 11.0.25, from 10.1.22 through 10.1.59, from 9.0.92 through 9.0.121. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

EUVD references (1)

https://lists.apache.org/thread/nmkmjp9l53y8h3oc4n8fc0bkw9dv15sk

Affected products (1)

Vendor	Product	Versions	Platforms
Apache Software Foundation	Apache Tomcat	`11.0.0-M14` (affected), `10.1.22` (affected), `9.0.92` (affected)	—

Vendor references (1)

References embedded in the original CVE record by the assigning CNA.

https://lists.apache.org/thread/nmkmjp9l53y8h3oc4n8fc0bkw9dv15sk vendor-advisory

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (1)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://lists.apache.org/thread/nmkmjp9l53y8h3oc4n8fc0bkw9dv15sk security@apache.org

Remediations (10)

CVE-2026-86248 - Vulnerability Details - OpenCVE

web:app.opencve.io

The vulnerability arises when Tomcat's client certificate authentication fails to reject connections that should be denied, even when the soft‑fail option is disabled. This flaw allows attackers to present a malformed or otherwise invalid certificate that is unknowingly accepted, providing unauthorized access to protected resources. The weakness lies in the certificate validation logic ...

2026-09-24 11:49 UTC
July 2026 Critical Patch Update Released | security - Oracle Blogs

web:blogs.oracle.com

For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.

2026-09-24 11:49 UTC
CVE-2026-86248: Apache Tomcat Improper Authentication

web:cvetodo.com

CVE-2026-86248 is a CVSS 9.8 Improper Authentication vulnerability in Apache Tomcat. See exploitation status, patch guidance, and technical details.

2026-09-24 11:49 UTC
CVE-2026-86248 — Apache Software Foundation Apache Tomcat | CyberSIXT

web:cybersixt.com

CVE-2026-86248 : CVSS 9.8 critical, affecting Apache Software Foundation Apache Tomcat. CLIENT_CERT authentication does not fail as expected for some scenarios when soft fail is disabled vulnerability in Apac

2026-09-24 11:49 UTC
CVE-2026-86248 - security-tracker.debian.org

web:security-tracker.debian.org

Vulnerable and fixed packages The table below lists information on source packages.

2026-09-24 11:49 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-24 11:49 UTC
What Is CVE Remediation in 2026? - aikido.dev

web:www.aikido.dev

CVE remediation is fixing known flaws in the software you run. Why upgrading often fails, what remediation actually involves, and how backporting fixes it.

2026-09-24 11:49 UTC
CVE: Common Vulnerabilities and Exposures

web:www.cve.org

At cve .org, we provide the authoritative reference method for publicly known information-security vulnerabilities and exposures

2026-09-24 11:49 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-24 11:49 UTC
Oracle Critical Patch Update Advisory - July 2026

web:www.oracle.com

This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-24 11:49 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-86248.json.

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