RabbitMQ up to 3.13.14/4.0.19/4.1.10/4.2.5 AMQP 1.0 Framing Parser rabbit_amqp_reader.erl parse_array_primitive Count resource consumption

Summaryinfo

A vulnerability was found in RabbitMQ up to 3.13.14/4.0.19/4.1.10/4.2.5. It has been declared as problematic. Affected by this issue is the function parse_array_primitive of the file rabbit_amqp_reader.erl of the component AMQP 1.0 Framing Parser. The manipulation of the argument Count results in resource consumption. This vulnerability is reported as CVE-2026-66079. The attack can be launched remotely. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in RabbitMQ up to 3.13.14/4.0.19/4.1.10/4.2.5. Affected is the function parse_array_primitive of the file rabbit_amqp_reader.erl of the component AMQP 1.0 Framing Parser. The manipulation of the argument Count with an unknown input leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. This is going to have an impact on availability. CVE summarizes:

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6, parse_array_primitive/2 for constructor 0x45 (list0) returns an element with byte-width B = 0. The enclosing array32 parser at line 148 reads a 4-byte Count from the wire and loops Count times consuming B bytes each , with B = 0, no input is consumed and the loop builds a list of Count empty elements bounded only by the 32-bit field. The SASL-mechanisms / SASL-init frame is parsed by amqp10_framing:decode_bin/1 from rabbit_amqp_reader.erl:412 before authentication completes. The pre-auth incoming_max_frame_size (default 8192 bytes) caps the frame, not the Count field, so a 19-byte payload with Count = 0xFFFFFFFF is accepted. No max_heap_size is set on the reader process. An unauthenticated network attacker can crash any RabbitMQ node that has the AMQP 1.0 listener enabled (default port 5672) by sending a single ~19-byte frame. The reader process attempts to build a list of ~4 billion empty elements, exhausting heap memory and terminating the Erlang VM. All tenants and protocols on the node lose service. Preconditions include Network reachability to the AMQP listener (port 5672, enabled by default) No authentication required. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-66079 since 07/24/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 3.13.15, 4.0.20, 4.1.11 or 4.2.6 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• RabbitMQ

Version

• 3.13.0
• 3.13.1
• 3.13.2
• 3.13.3
• 3.13.4
• 3.13.5
• 3.13.6
• 3.13.7
• 3.13.8
• 3.13.9
• 3.13.10
• 3.13.11
• 3.13.12
• 3.13.13
• 3.13.14
• 4.0.0
• 4.0.1
• 4.0.2
• 4.0.3
• 4.0.4
• 4.0.5
• 4.0.6
• 4.0.7
• 4.0.8
• 4.0.9
• 4.0.10
• 4.0.11
• 4.0.12
• 4.0.13
• 4.0.14
• 4.0.15
• 4.0.16
• 4.0.17
• 4.0.18
• 4.0.19
• 4.1.0
• 4.1.1
• 4.1.2
• 4.1.3
• 4.1.4
• 4.1.5
• 4.1.6
• 4.1.7
• 4.1.8
• 4.1.9
• 4.1.10
• 4.2.0
• 4.2.1
• 4.2.2
• 4.2.3
• 4.2.4
• 4.2.5

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

Discussion