CVE-2020-14000

MIT Lifelong Kindergarten Scratch scratch-vm before 0.2.0-prerelease.20200714185213 loads extension URLs from untrusted project.json files with certain _ characters, resulting in remote code execution because the URL's content is treated as a script and is executed as a worker. The responsible code is getExtensionIdForOpcode in serialization/sb3.js. The use of _ is incompatible with a protection mechanism in older versions, in which URLs were split and consequently deserialization attacks were prevented. NOTE: the scratch.mit.edu hosted service is not affected because of the lack of worker scripts.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 7.5 HIGH

9.8^/10

CVSS v3.0 : CRITICAL

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

V2 Legend

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://github.com/LLK/scratch-vm/pull/2476	Third Party Advisory
https://scratch.mit.edu/discuss/topic/422904/?page=1#post-4223443	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mit:scratch-vm:*:*:*:*:*:*:*:*

Information

Published : 2020-07-16 08:15

Updated : 2020-07-24 08:02

NVD link : CVE-2020-14000

Mitre link : CVE-2020-14000

JSON object : View

CWE

CWE-502

Deserialization of Untrusted Data

Products Affected

mit

scratch-vm

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9.8 /10