UnrealIRCd up to 6.2.6 Webserver denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in UnrealIRCd up to 6.2.6. Impacted is an unknown function of the component Webserver. Executing a manipulation can lead to denial of service. This vulnerability is registered as CVE-2026-90668. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in UnrealIRCd up to 6.2.6. This vulnerability affects an unknown part of the component Webserver. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. CVE summarizes:

The webserver in UnrealIRCd 6.0.5 through 6.2.6 before 6.2.7 does not limit the number of HTTP request headers, which allows remote attackers to cause a denial of service (memory consumption and unresponsive server) via an HTTP request with an unlimited number of headers, if a websocket or JSON-RPC listener is enabled (disabled by default).

The advisory is available at unrealircd.org. This vulnerability was named CVE-2026-90668 since 09/13/2026. 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. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 6.2.7 eliminates this vulnerability.

The vulnerability is also documented in the databases at CNNVD (CNNVD-2026-98846824) and EUVD (EUVD-2026-76937). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

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: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

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

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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: UnrealIRCd 6.2.7

Timelineinfo

09/13/2026 Advisory disclosed
09/13/2026 +0 days CVE reserved
09/13/2026 +0 days VulDB entry created
09/14/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: unrealircd.org
Status: Confirmed

CVE: CVE-2026-90668 (🔒)
GCVE (CVE): GCVE-0-2026-90668
GCVE (VulDB): GCVE-100-403210
EUVD: 🔒
CNNVD: CNNVD-2026-98846824 - UnrealIRCd 资源管理错误漏洞

Entryinfo

Created: 09/13/2026 04:34
Updated: 09/14/2026 18:09
Changes: 09/13/2026 04:34 (77), 09/13/2026 06:30 (1), 09/14/2026 18:09 (6)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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