CVE-2022-30591 in quic-go
Summary
by MITRE • 07/06/2022
** DISPUTED ** quic-go through 0.27.0 allows remote attackers to cause a denial of service (CPU consumption) via a Slowloris variant in which incomplete QUIC or HTTP/3 requests are sent. This occurs because mtu_discoverer.go misparses the MTU Discovery service and consequently overflows the probe timer. NOTE: the vendor's position is that this behavior should not be listed as a vulnerability on the CVE List.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 08/03/2024
The vulnerability described in CVE-2022-30591 pertains to the quic-go library version 0.27.0 and earlier, where a remote attacker can induce a denial of service condition through a Slowloris-style attack variant targeting the QUIC and HTTP/3 protocols. This issue manifests when incomplete requests are transmitted to the affected system, creating a scenario where the MTU discovery mechanism fails to properly parse the service, leading to excessive CPU consumption. The core technical flaw resides in the mtu_discoverer.go component which incorrectly handles the MTU discovery process, resulting in probe timer overflow conditions that can be exploited to exhaust system resources.
The operational impact of this vulnerability extends beyond simple resource exhaustion, as it represents a sophisticated attack vector that leverages protocol-specific weaknesses in the QUIC implementation. The Slowloris variant employed in this attack maintains persistent connections by sending partial requests that never complete, causing the server to continuously attempt to process these incomplete requests. This behavior aligns with attack patterns documented in the MITRE ATT&CK framework under the category of resource exhaustion attacks, specifically targeting network services through connection manipulation techniques. The vulnerability demonstrates how protocol implementation details can create unintended attack surfaces that adversaries can exploit to consume system resources without requiring sophisticated privileges or direct access to the underlying system.
From a cybersecurity perspective, this vulnerability highlights the importance of proper input validation and resource management in protocol implementations, particularly in high-performance networking libraries that handle multiple concurrent connections. The MTU discovery mechanism, designed to optimize network performance by determining the maximum transmission unit size, becomes a point of failure when not properly implemented to handle malformed or incomplete requests. This flaw demonstrates how seemingly benign protocol features can become attack vectors when not adequately protected against malformed input or prolonged connection states. The vulnerability also underscores the complexity of modern network protocols like QUIC and HTTP/3, where implementation details can create unexpected security implications that may not be immediately obvious during initial protocol design phases.
The vendor's position that this behavior should not be listed as a vulnerability on the CVE List reflects ongoing debates within the cybersecurity community regarding what constitutes a legitimate vulnerability versus expected protocol behavior. This stance suggests that the issue may be classified as a design limitation or expected behavior rather than a security flaw, though the practical impact remains significant for system administrators and security practitioners. The classification debate mirrors discussions around CWE (Common Weakness Enumeration) categories, where certain implementation details may not meet the threshold for vulnerability classification despite causing measurable operational impact. Organizations implementing quic-go libraries should consider this vulnerability as a potential risk requiring monitoring and mitigation strategies, particularly in environments where resource exhaustion attacks could be leveraged to disrupt service availability.