CVE-2026-92790: Higress before 2.2.4 Rate Limit Bypass via Malformed Cookie Header
Higress before 2.2.4 panics when processing a Cookie header segment without an equals sign, causing the plugin wrapper to recover and return a continue action that bypasses AI token rate limiting. Unauthenticated attackers can craft a malformed Cookie header to skip rate limit checks and exceed thresholds intended to restrict costly model backend calls.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Higressto a version that resolves this vulnerability.Fixed in 2.2.4 - Compensating control
Until Higress is upgraded to 2.2.4, deploy a compensating control that blocks or rejects requests containing malformed Cookie header segments lacking an equals sign (rate-limit bypass attempt), e.g., via a WAF/header validation at the edge.
Event History
Frequently Asked Questions
Which deployments are exposed?
Higress deployments running a version before 2.2.4 are affected where the AI token rate limiting functionality is in use. The bypass targets rate limits intended to constrain costly model backend calls.
What does an attacker need to exploit this issue?
An attacker only needs network access to send requests to the affected Higress service. No authentication or user interaction is required; the request includes a Cookie header segment without an equals sign.
What is the impact of successful exploitation?
The malformed Cookie segment causes processing to panic, after which the plugin wrapper recovers and continues the request instead of enforcing the AI token rate limit. An attacker can therefore exceed configured token thresholds and drive additional model backend usage.