RabbitMQ: Consistent-hash exchange unbounded weight
RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, add_binding/3 parses the routing key as an integer weight N and computes ring positions with lists:seq(NextN0, NextN0 + N - 1). validate_binding/2 only checks N >= 1 , no upper bound. The resulting list is stored in the exchange's Khepri record, replicated cluster-wide, and reloaded on restart. A user with write permission on a consistent-hash exchange and read on a queue can create a binding whose routing key (the hash-ring weight) is an arbitrarily large integer. The broker allocates a list of that many integers via lists:seq/2 and persists it to Khepri across all cluster nodes , a single binding with weight 100000000 allocates ~800 MB on every node and survives restarts. Preconditions include rabbitmq_consistent_hash_exchange plugin enabled write permission on a consistent-hash exchange + read on a queue (standard binding perms). This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0.
CVE-2026-67219
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-67219
rabbitmq-server
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "rabbitmq",
"product": "rabbitmq-server",
"versions": [
{
"status": "affected",
"version": ">= 3.13.0, < 3.13.15"
},
{
"status": "affected",
"version": ">= 4.0.0, < 4.0.20"
},
{
"status": "affected",
"version": ">= 4.1.0, < 4.1.11"
},
{
"status": "affected",
"version": ">= 4.2.0, < 4.2.6"
}
]
}
]- Related CVEs
- CVE-2026-67219
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #921 · Revision 1
- Added to Heist Feed
- Publisher date