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… (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).
AI Analysis
Technical Summary
The webserver in UnrealIRCd versions 6.0.5 through 6.2.6 before 6.2.7 does not impose limits on the number of HTTP request headers it accepts. Remote attackers can exploit this by sending HTTP requests containing an unlimited number of headers, causing excessive memory usage and rendering the server unresponsive. This denial of service condition requires that either the websocket or JSON-RPC listener feature is enabled, both of which are disabled by default.
Potential Impact
Remote attackers can cause a denial of service on affected UnrealIRCd servers by exhausting memory resources and making the server unresponsive. There is no impact on confidentiality or integrity. The attack surface is limited to servers with websocket or JSON-RPC listeners enabled.
Mitigation Recommendations
Upgrade UnrealIRCd to version 6.2.7 or later where this issue is fixed. If upgrading is not immediately possible, ensure that websocket and JSON-RPC listeners remain disabled (the default setting) to mitigate exposure. Monitor vendor advisories for official patches or updates.
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… (CVE-2026-90668)
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 v3.1
Score 7.5high
Affected software
pkg:github/unrealircd/unrealircdRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The webserver in UnrealIRCd versions 6.0.5 through 6.2.6 before 6.2.7 does not impose limits on the number of HTTP request headers it accepts. Remote attackers can exploit this by sending HTTP requests containing an unlimited number of headers, causing excessive memory usage and rendering the server unresponsive. This denial of service condition requires that either the websocket or JSON-RPC listener feature is enabled, both of which are disabled by default.
Potential Impact
Remote attackers can cause a denial of service on affected UnrealIRCd servers by exhausting memory resources and making the server unresponsive. There is no impact on confidentiality or integrity. The attack surface is limited to servers with websocket or JSON-RPC listeners enabled.
Mitigation Recommendations
Upgrade UnrealIRCd to version 6.2.7 or later where this issue is fixed. If upgrading is not immediately possible, ensure that websocket and JSON-RPC listeners remain disabled (the default setting) to mitigate exposure. Monitor vendor advisories for official patches or updates.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-fj9c-wr2v-556h
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-90668"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6aa741ab55bf5e2cf548a60d
Added to database: 09/14/2026, 00:36:59 UTC
Last enriched: 09/14/2026, 00:44:39 UTC
Last updated: 09/14/2026, 02:08:38 UTC
Views: 5
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