CVE-2020-7637

Name: CVE-2020-7637
Creator: NVD / NIST
Published: 2020-04-06T13:15:12.55+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 1.16%

Last modified Jun 17, 2026

CVE-2020-7637 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. class-transformer before 0.3.1 allow attackers to perform Prototype Pollution. The classToPlainFromExist function could be tricked into adding or modifying properties of Object.prototype using a __proto__ payload.. EPSS estimates a 1.16% chance of exploitation in the next 30 days.

Description

class-transformer before 0.3.1 allow attackers to perform Prototype Pollution. The classToPlainFromExist function could be tricked into adding or modifying properties of Object.prototype using a __proto__ payload.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS Probability

1.16%

63.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-1321

Affected Software

Vendor	Product	Versions
Class-Transformer Project	Class-Transformer	< 0.3.1

References

https://github.com/typestack/class-transformer/commit/8f04eb9db02de708f1a20f6f2d2bb309b2fed01ePatch, Third Party Advisory
https://snyk.io/vuln/SNYK-JS-CLASSTRANSFORMER-564431Exploit, Third Party Advisory
https://github.com/typestack/class-transformer/commit/8f04eb9db02de708f1a20f6f2d2bb309b2fed01ePatch, Third Party Advisory
https://snyk.io/vuln/SNYK-JS-CLASSTRANSFORMER-564431Exploit, Third Party Advisory

Timeline

Published: Apr 6, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-7637?

How severe is CVE-2020-7637?

CVE-2020-7637 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 1.16% probability of exploitation in the next 30 days.

How do I fix CVE-2020-7637?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-7637?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST