Description
Consul and Consul Enterprise are vulnerable to a denial of service in the native RPC listener that may allow an authenticated client to exhaust server memory before ACL authorization is evaluated. A client that can complete the internal RPC mTLS handshake may exploit this issue without holding a valid ACL token. This vulnerability (CVE-2026-87106) is fixed in Consul 2.0.4 and Consul Enterprise 1.21.18, 1.22.12 and 2.0.4.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| HashiCorp | Consul | 1.21.0 – < 2.0.4 | 2.0.4 |
| HashiCorp | Consul Enterprise | 1.21.0 – < 2.0.4 | 2.0.4 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | consul | No fix yet | — |
| Ubuntu 20.04 LTS | consul | No fix yet | — |
| Ubuntu 18.04 LTS | consul | No fix yet | — |