CVE-2026-55157Public exploitHinoki check available

Command execution via smart_user username shell interpolation

Published Sep 28, 2026 · Updated Sep 28, 2026

OS command injection in Ooples Token Optimizer MCP before 5.1.0 allows attackers to execute commands through the smart_user username argument. The get-user-info operation inserts that argument into a shell command without neutralizing shell syntax; POSIX command substitution runs even inside double quotes. An attacker must be able to call the local MCP tool, and injected commands run with the server user's privileges.

CVSS severity8.4
High
EPSS probability0.70%
Next 30 days · Oct 18, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

OS command injection in Ooples Token Optimizer MCP before 5.1.0 allows attackers to execute commands through the smart_user username argument. The get-user-info operation inserts that argument into a shell command without neutralizing shell syntax; POSIX command substitution runs even inside double quotes. An attacker must be able to call the local MCP tool, and injected commands run with the server user's privileges.

The record

CVE
CVE-2026-55157
Published
Sep 28, 2026
Updated
Sep 28, 2026
Vendor
Ooples
Product
Token Optimizer MCP
Classifications
CWE-78, T1059
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 28, 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=< 5.1.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Ooples · Token Optimizer MCPversion=< 5.1.0

Published CVSS scores

8.4GitHub Advisory DatabaseCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

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

Technologies

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