CVE-2020-28503Public exploitNetwork attack vector

Inherited property modification via unsafe deep copy

Published Mar 23, 2021 · Updated Sep 17, 2024

Prototype pollution in Gulp.js copy-props before 2.0.5 allows remote attackers to alter inherited object properties through crafted keys. The _setDeep routine recursively processes proto and constructor path elements without rejecting prototype-sensitive keys. Exploitation requires a consuming application to pass attacker-controlled property paths or object keys to the copy routine; downstream effects depend on how inherited properties are used.

CVSS severity7.3
High
EPSS probability1.70%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Prototype pollution in Gulp.js copy-props before 2.0.5 allows remote attackers to alter inherited object properties through crafted keys. The _setDeep routine recursively processes proto and constructor path elements without rejecting prototype-sensitive keys. Exploitation requires a consuming application to pass attacker-controlled property paths or object keys to the copy routine; downstream effects depend on how inherited properties are used.

The record

CVE
CVE-2020-28503
Published
Mar 23, 2021
Updated
Sep 17, 2024
Vendor
Gulp.js
Product
copy-props
Classifications
CWE-1321
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2024Record 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=unspecified <2.0.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Gulp.js · copy-propsversion=unspecified <2.0.5

Published CVSS scores

9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.3SnykCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
6.6SnykCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O
7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

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.

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

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

Public exploit references

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

Technologies

Your stack

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Your stack

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