CVE Intelligence
Critical

CVE-2026-16326 — consul-mcp-server vulnerable to cross-tenant credential reuse in streamable-HTTP stateless mode

In consul-mcp-server, versions 0.1.0 up to 0.1.3 did not properly isolate session state in stateless mode, which may allow one client's Consul authentication token to be used for subsequent requests from other clients. This vulnerability (CVE-2026-16326) is fixed in consul-mcp-server 0.1.4.

Published Jul 29, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: HashiCorp

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.5% (30-day exploitation probability)+7
  • Technical severity (critical)+10
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.54%
ahead of 44% of scored CVEs · Oct 15, 2026
Affects
HashiCorp
Tooling
CVSS base
10.0
Critical · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (HashiCorp Tooling).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
HashiCorp Tooling ≥ 0.1.0 and < 0.1.4 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
Low

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
10.0 CVSS 3.1 Critical 3.9 6.0 security@hashicorp.com via NIST National Vulnerability Database
10.0 CVSS 3.1 Critical — — HashiCorp via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L (score shown at the top: security@hashicorp.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-488

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · hashicorp/tooling
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 15, 2026
  • CVSS changed · 10.0
    Oct 15, 2026 · NIST National Vulnerability Database
  • Source status changed · → Deferred
    Oct 15, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 15, 2026 · NIST National Vulnerability Database
  • CVE published
    Jul 29, 2026 · HashiCorp

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

1 on the record

Elsewhere on this site

HashiCorp
every CVE for this vendor
CWE-488
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-87993 Consul-template vulnerable to an information disclosure issue in error handling Sep 10, 2026
  • CVE-2026-8715 Vault Secrets Operator vulnerable to arbitrary file read and credential exfiltration via AppRole secretIDPath Aug 13, 2026
  • CVE-2026-16328 consul-mcp-server vulnerable to server side request forgery leading to token exposure Jul 29, 2026
  • CVE-2026-16498 terraform-mcp-server vulnerable to cross-tenant credential reuse in streamable-HTTP stateless mode Jul 28, 2026
  • CVE-2026-14869 terraform-mcp-server vulnerable to server side request forgery leading to token exposure Jul 28, 2026
  • CVE-2026-16496 terraform-mcp-server vulnerable to cross-user credential inheritance if an MCP session ID is obtained by another user Jul 28, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-16326 is "consul-mcp-server vulnerable to cross-tenant credential reuse in streamable-HTTP stateless mode", rated Critical. It affects Tooling (HashiCorp); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 10.0 describes technical severity. EPSS 0.54% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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