Netty up to 4.2.17.Final QUIC Certificate Verification certificate validation

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00+

Summaryinfo

A vulnerability classified as problematic was found in Netty up to 4.2.17.Final. This affects an unknown function of the component QUIC Certificate Verification. Executing a manipulation can lead to certificate validation. The identification of this vulnerability is CVE-2026-100665. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Netty up to 4.2.17.Final. It has been declared as problematic. This vulnerability affects an unknown function of the component QUIC Certificate Verification. The manipulation with an unknown input leads to a certificate validation vulnerability. The CWE definition for the vulnerability is CWE-295. The product does not validate, or incorrectly validates, a certificate. As an impact it is known to affect integrity. CVE summarizes:

Netty versions from 4.2.11.Final before 4.2.18.Final contain an incomplete hostname verification fix in the QUIC certificate verification path when using a plain X509TrustManager. The BoringSSLCertificateVerifyCallback discards the SSLEngine for plain trust managers, preventing endpoint identification from running even when HTTPS verification is configured. Attackers on the network path can present a certificate chain for the wrong hostname that the plain trust manager accepts, bypassing hostname authentication for QUIC clients.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-100665 since 09/26/2026. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1587.003.

Upgrading to version 4.2.18.Final eliminates this vulnerability.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Certificate validation
CWE: CWE-295 / 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: Netty 4.2.18.Final

Timelineinfo

09/26/2026 Advisory disclosed
09/26/2026 +0 days CVE reserved
09/26/2026 +0 days VulDB entry created
09/26/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-100665 (🔒)
GCVE (CVE): GCVE-0-2026-100665
GCVE (VulDB): GCVE-100-410704

Entryinfo

Created: 09/26/2026 16:30
Changes: 09/26/2026 16:30 (75)
Complete: 🔍
Cache ID: 216::103

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