CVE-2026-87106Network attack vector

Server termination via unbounded RPC header decoding

Published Sep 10, 2026 · Updated Sep 10, 2026

Resource exhaustion in HashiCorp Consul and Consul Enterprise 1.21.0 through 2.0.3 allows remote authenticated users to terminate servers. The native RPC request decoder accepts oversized header data without enforcing a size limit, allocating excessive memory before method validation or ACL evaluation. Exploitation requires reachability to TCP port 8300 and a client certificate trusted by the internal RPC CA, but no ACL token; process termination interrupts control-plane operations.

CVSS severity6.5
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in HashiCorp Consul and Consul Enterprise 1.21.0 through 2.0.3 allows remote authenticated users to terminate servers. The native RPC request decoder accepts oversized header data without enforcing a size limit, allocating excessive memory before method validation or ACL evaluation. Exploitation requires reachability to TCP port 8300 and a client certificate trusted by the internal RPC CA, but no ACL token; process termination interrupts control-plane operations.

The record

CVE
CVE-2026-87106
Published
Sep 10, 2026
Updated
Sep 10, 2026
Vendor
HashiCorp
Product
Consul Enterprise
Classifications
CWE-400, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.21.0 <2.0.4 changes=[{"at":"1.21.18","status":"unaffected"},{"at":"1.22.12","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

HashiCorp · Consul Enterpriseversion=1.21.0 <2.0.4 changes=[{"at":"1.21.18","status":"unaffected"},{"at":"1.22.12","status":"unaffected"}]
HashiCorp · Consulversion=1.21.0 <2.0.4

Published CVSS scores

6.5HashiCorpCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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