CVE-2021-4258Network attack vector

Package-data exposure via unencrypted repository requests

Published Dec 19, 2022 · Updated Apr 15, 2025

Cleartext transmission in whohas allows man-in-the-middle attackers to read package-query data through unencrypted repository requests. Hard-coded HTTP base URLs in multiple package handlers send queries without transport confidentiality or integrity, and returned pages are parsed for display. A network path position is required to read queries or manipulate displayed package information; the claim remains disputed because most endpoints redirect to HTTPS.

CVSS severity7.5
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cleartext transmission in whohas allows man-in-the-middle attackers to read package-query data through unencrypted repository requests. Hard-coded HTTP base URLs in multiple package handlers send queries without transport confidentiality or integrity, and returned pages are parsed for display. A network path position is required to read queries or manipulate displayed package information; the claim remains disputed because most endpoints redirect to HTTPS.

The record

CVE
CVE-2021-4258
Published
Dec 19, 2022
Updated
Apr 15, 2025
Vendor
Philipp Wesche
Product
whohas
Classifications
CWE-319, CWE-310, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 19, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 15, 2025Record 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=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Philipp Wesche · whohasversion=n/a

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
3.7VulDBCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A: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-319Cleartext Transmission of Sensitive Information
CWE-310Cryptographic Issues
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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