CVE-2026-90668

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).

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://forums.unrealircd.org/viewtopic.php?t=9483
https://www.unrealircd.org/

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-13 02:17

Updated : 2026-09-14 19:18

NVD link : CVE-2026-90668

Mitre link : CVE-2026-90668

CVE.ORG link : CVE-2026-90668

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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