Vulnerability · Published Sep 10, 2026 · Assigned by HashiCorp
CVE-2026-88021Consul vulnerable to an authorization bypass in the Connect service mesh
High 7.5
In plain English
A high-severity security flaw in Consul from HashiCorp. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities).
Official description
Consul and Consul Enterprise are vulnerable to an authorization bypass in the Connect service mesh that may allow a service to reach a destination it is not authorized to access. When building Envoy RBAC rules to enforce Connect intentions, Consul did not correctly escape certain characters in service names, namespaces, and partitions, causing the generated authorization rules to match more broadly than intended. This vulnerability (CVE-2026-88021) is fixed in Consul 2.0.4 and Consul Enterprise 1.21.18, 1.22.12 and 2.0.4.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu:22.04:LTS | consul | no fix listed | UBUNTU-CVE-2026-88021 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| HashiCorp | Consul | 1.9.0 – before 2.0.4 |
| HashiCorp | Consul Enterprise | 1.9.0 – before 2.0.4 |
Weakness: CWE-185 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N