CVE-2026-79921 in amqp091-go
Summary
by MITRE • 08/27/2026
amqp091-go is a Go AMQP 0.9.1 client. Before version 1.13.0, a compromised or malicious AMQP broker can force the client to allocate resources for and process content body frames that exceed the negotiated frame_max limit. This can lead to unexpected memory consumption or application-layer denial of service (DoS), bypassing the protocol's built-in framing constraints. Version 1.13.0 contains a fix. No known workarounds are available.
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Analysis
by VulDB Data Team • 08/27/2026
The amqp091-go library serves as a widely utilized implementation for interacting with AMQP 0.9.1 compliant message brokers in Go-based applications. A critical vulnerability exists within versions prior to 1.13.0, where the client fails to strictly enforce the frame_max parameter negotiated during connection setup. In the Advanced Message Queuing Protocol (AMQP), the frame_max value defines the maximum size of a single frame that can be transmitted over the connection. This negotiation is intended to prevent any single party from overwhelming the other with excessively large data chunks, thereby ensuring stable resource utilization and predictable performance characteristics for both client and server components.
The technical flaw lies in the parsing logic of content body frames within the library's implementation. When a malicious or compromised AMQP broker sends content body frames that exceed the negotiated frame_max limit, the vulnerable version of amqp091-go does not reject these oversized frames as required by the protocol specification. Instead, it proceeds to allocate memory and process the entire payload regardless of its size relative to the agreed-upon constraint. This behavior effectively bypasses the built-in framing constraints designed to protect against resource exhaustion attacks, allowing an attacker to dictate the amount of system resources consumed by the client application.
The operational impact of this vulnerability is significant, primarily manifesting as a potential denial of service condition through unexpected memory consumption. By forcing the client to allocate large blocks of heap memory for processing oversized frames, an attacker can rapidly deplete available RAM on the host machine. This resource exhaustion can lead to the termination of the Go application by the operating system's out-of-memory killer or cause severe performance degradation due to excessive garbage collection pauses and swapping. Consequently, this flaw enables a remote denial of service attack against applications relying on amqp091-go for message queue connectivity, undermining the availability aspect of the CIA triad without requiring authentication if the broker is accessible.
This vulnerability aligns with CWE-787: Out-of-bounds Write in terms of resource allocation logic and more specifically relates to CWE-400: Uncontrolled Resource Consumption. From a threat intelligence perspective, this behavior facilitates attacks categorized under MITRE ATT&CK technique T1499: Endpoint Denial of Service, where the attacker aims to disrupt service availability by exhausting system resources rather than compromising data integrity or confidentiality directly. The lack of input validation against negotiated protocol limits represents a fundamental failure in enforcing security boundaries defined during session initialization.
Mitigation for this issue requires upgrading the amqp091-go dependency to version 1.13.0 or later, which contains the necessary code changes to properly validate frame sizes against the negotiated frame_max limit before allocation and processing occur. Since no known workarounds are available at the application configuration level, relying on network-level controls such as firewalls or intrusion detection systems is insufficient because these tools typically inspect packet headers rather than application-layer protocol semantics like AMQP frame boundaries. Organizations should prioritize patching this library across all services that utilize it for messaging to restore compliance with AMQP security expectations and prevent potential resource exhaustion attacks from malicious brokers or compromised intermediaries in the message routing infrastructure.