Medium severity · published Sep 10, 2026
CVE-2026-87106
Consul vulnerable to a denial of service in the native RPC listener
6.5
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
Consul · HashiCorp
1.21.0 before 2.0.4 · source: vendor
CE
Consul Enterprise · HashiCorp
1.21.0 before 2.0.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-87106
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-87106
discuss.hashicorp.com
https://discuss.hashicorp.com/t/hcsec-2026-35-consul-vulnerable-to-a-denial-of-service-in-the-native-rpc-listener/77737
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