How severe is CVE-2026-18655?

CVE-2026-18655 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-18655 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-18655?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-18655 published?

CVE-2026-18655 was published on 2026-08-03 and last updated on 2026-08-04.

CVE-2026-18655

CVE-2026-18655 is a medium-severity vulnerability with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-923.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 7.1
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-923
Published: 2026-08-03
Last modified: 2026-08-04

Description

Improper restriction of intended endpoints in the RabbitMQ broker connection tools of the Amazon MQ MCP Server (awslabs.amazon-mq-mcp-server) before 2.0.24 may allow a remote unauthenticated actor (via prompt injection) to obtain Amazon MQ for RabbitMQ broker credentials or OAuth access tokens sent to a crafted endpoint controlled through a broker hostname introduced in the MCP client context. To remediate this issue, users should upgrade to version 2.0.24.

Frequently asked questions

What is CVE-2026-18655?: Improper restriction of intended endpoints in the RabbitMQ broker connection tools of the Amazon MQ MCP Server (awslabs.amazon-mq-mcp-server) before 2.0.24 may allow a remote unauthenticated actor (via prompt injection) to obtain Amazon MQ for RabbitMQ broker credentials or OAuth access tokens sent to a crafted endpoint controlled through a broker hostname introduced in the MCP client context. To remediate this issue, users should upgrade to version 2.0.24.
How severe is CVE-2026-18655?: CVE-2026-18655 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-18655 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-18655?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-18655 published?: CVE-2026-18655 was published on 2026-08-03 and last updated on 2026-08-04.

References

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