9.8

CVE-2020-14000: mit scratch-vm Deserialization of Untrusted Data

CVSS: 9.8v3.1CriticalModified
AliasesGHSA-vc9j-fhvv-8vrf
Published 16-07-2020Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2020-14000 is a critical (CVSS 9.8) Deserialization of Untrusted Data vulnerability in mit scratch-vm. EPSS estimates a 2.83% chance of exploitation in the next 30 days, higher than 86.4% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (NVD)
EPSS score
2.83%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 16-07-2020
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

Description

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 metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

2.83%

Chance of exploitation in the next 30 days

Percentile

86%

Versus all other CVEs

30-day change

0.00 pp

From 2.83% on 18-09-2026

18-09-202618-10-2026
EPSS score
2.83%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Mit1 product
Npm1 product
  • scratch-vm< 0.2.0-prerelease.20200714185213

2 vendors · 2 products

References

5 links