elct9620 Kobako up to 0.9.0 sandbox

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.5$0-$5k0.15

Summaryinfo

A vulnerability marked as critical has been reported in elct9620 Kobako up to 0.9.0. This impacts an unknown function. Performing a manipulation results in sandbox. This vulnerability is identified as CVE-2026-55107. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in elct9620 Kobako up to 0.9.0. This affects an unknown code. The manipulation with an unknown input leads to a sandbox vulnerability. CWE is classifying the issue as CWE-265. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Kobako is a Ruby gem that embeds a Wasm-isolated mruby interpreter inside applications, allowing execution of untrusted Ruby scripts (LLM-generated code, user formulas, student submissions, third-party plugins) in-process without giving them access to host memory, files, network, or credentials. From version 0.1.0 to before version 0.9.1, a guest mruby script running inside the Kobako sandbox can execute arbitrary Ruby in the host process, fully escaping the sandbox. This issue has been patched in version 0.9.1.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-55107 since 06/16/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1611 according to MITRE ATT&CK.

Upgrading to version 0.9.1 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.6
VulDB Meta Temp Score: 8.5

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 10.0
CNA Vector (GitHub_M): 🔒

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Sandbox
CWE: CWE-265 / CWE-264
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kobako 0.9.1

Timelineinfo

06/16/2026 CVE reserved
09/30/2026 +106 days Advisory disclosed
09/30/2026 +0 days VulDB entry created
09/30/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-55107 (🔒)
GCVE (CVE): GCVE-0-2026-55107
GCVE (VulDB): GCVE-100-412311

Entryinfo

Created: 09/30/2026 19:29
Changes: 09/30/2026 19:29 (63)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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