Login Request a demo
High severity · published Sep 13, 2026
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…
7.5
CVSS
0.6%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 48% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
UN
UnrealIRCd · UnrealIRCd
6.0.5 before 6.2.7 · source: vendor
Affected product
UN
UnrealIRCd
UnrealIRCd
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-90668
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-90668
forums.unrealircd.org
https://forums.unrealircd.org/viewtopic.php?t=9483
www.unrealircd.org
https://www.unrealircd.org/
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