CVE-2026-18997Public exploitNetwork attack vector

Authenticated command execution via unguarded background shell

Published Aug 6, 2026 · Updated Aug 6, 2026

Incorrect authorization in Cosmic Stack Mercury Agent 1.1.0 through 1.1.12 allows remote authenticated users to execute host commands. Agent.handleBgCommand forwards the raw /bg command to spawnShell, which invokes a real shell without calling PermissionManager.checkShellCommand. A valid dashboard session is required, and commands run with the Mercury process account's access to the workspace, configuration, and host resources.

CVSS severityUnavailable

Unscored

EPSS probability0.21%

Next 30 days · Sep 16, 2026

Known exploitationUnconfirmed

Based on sourced intelligence

Hinoki checkNot available

Coverage for this vulnerability

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Summary

What happened

The record

CVE: CVE-2026-18997
Published: Aug 6, 2026
Updated: Aug 6, 2026

Vendor: Cosmic Stack
Product: Mercury Agent
Classifications: CWE-285, CWE-863, T1059

Attack vector: network
Privileges: authenticated

Timeline

How it unfolded

Aug 6, 2026CVE publishedPublication date reported by the CVE source.
Aug 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

Affected versionversion=1.1.0
Affected versionversion=1.1.1
Affected versionversion=1.1.10
Affected versionversion=1.1.11
Affected versionversion=1.1.12
Affected versionversion=1.1.2
Affected versionversion=1.1.3
Affected versionversion=1.1.4
Affected versionversion=1.1.5
Affected versionversion=1.1.6
Affected versionversion=1.1.7
Affected versionversion=1.1.8
Affected versionversion=1.1.9

What conditions does exploitation require?

Attack vectornetwork

Required privilegesauthenticated

What is affected?

Cosmic Stack · Mercury Agentversion=1.1.0; version=1.1.1; version=1.1.10; version=1.1.11; version=1.1.12; version=1.1.2; version=1.1.3; version=1.1.4; version=1.1.5; version=1.1.6; version=1.1.7; version=1.1.8; version=1.1.9

Published CVSS scores

5.3VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

6.5VulDBAV:N/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:ND/RC:UR

6.3VulDBCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R

6.3VulDBCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitPublished

Weakness, pattern, technique

CWE-285Improper Authorization

CWE-863Incorrect Authorization

T1059Command and Scripting Interpreter

Public exploit references

Mercury Agent /bg verification testfunctional · demonstrated

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

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