Apache Tomcat up to 11.0.25/10.1.59/9.0.121 CLIENT_CERT Authentication improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k0.91

Summaryinfo

A vulnerability categorized as critical has been discovered in Apache Tomcat up to 11.0.25/10.1.59/9.0.121. This impacts an unknown function of the component CLIENT_CERT Authentication. Executing a manipulation can lead to improper authentication. The identification of this vulnerability is CVE-2026-86248. The attack may be launched remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Apache Tomcat up to 11.0.25/10.1.59/9.0.121. This vulnerability affects an unknown functionality of the component CLIENT_CERT Authentication. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at lists.apache.org. This vulnerability was named CVE-2026-86248 since 09/06/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 09/23/2026).

Upgrading to version 11.0.26, 10.1.60 or 9.0.122 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Tomcat 11.0.26/10.1.60/9.0.122

Timelineinfo

09/06/2026 CVE reserved
09/23/2026 +17 days Advisory disclosed
09/23/2026 +0 days VulDB entry created
09/23/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apache.org

Advisory: lists.apache.org
Status: Confirmed

CVE: CVE-2026-86248 (🔒)
GCVE (CVE): GCVE-0-2026-86248
GCVE (VulDB): GCVE-100-408934

Entryinfo

Created: 09/23/2026 13:53
Changes: 09/23/2026 13:53 (55)
Complete: 🔍
Cache ID: 216::103

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