CVE-2021-3840Network attack vector

Code execution via public dependency substitution

Published Nov 12, 2021 · Updated Aug 3, 2024

Dependency confusion in Antilles before 1.0.1 allows remote attackers to execute code when a user installs affected components. Four component requirements.txt files named the unpublished antilles-tools dependency without restricting resolution to an Antilles-controlled source. Exploitation requires an attacker-controlled package to win dependency resolution and a user to install the affected software, after which package installation executes attacker-supplied code.

CVSS severity8.8
High
EPSS probability2.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Dependency confusion in Antilles before 1.0.1 allows remote attackers to execute code when a user installs affected components. Four component requirements.txt files named the unpublished antilles-tools dependency without restricting resolution to an Antilles-controlled source. Exploitation requires an attacker-controlled package to win dependency resolution and a user to install the affected software, after which package installation executes attacker-supplied code.

The record

CVE
CVE-2021-3840
Published
Nov 12, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-427, T1195.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 12, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8Lenovo Group Ltd.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.7GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-427Uncontrolled Search Path Element
T1195.001Compromise Software Dependencies and Development Tools

Public exploit references

No public exploit references are available in this record.

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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