CVE-2021-21251Public exploitNetwork attack vector

Authenticated arbitrary file write via unchecked tar paths

Published Jan 15, 2021 · Updated Aug 3, 2024

Path traversal in OneDev before 4.0.3 allows remote authenticated users to write arbitrary server files through a crafted tar upload. The KubernetesResource upload-outcomes endpoint passes request-body tar data to TarUtils.untar, which extracts entries without confining their paths to the workspace. A valid JobToken is required; successful traversal can overwrite files outside the intended extraction directory.

CVSS severity7.7
High
EPSS probability12.68%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in OneDev before 4.0.3 allows remote authenticated users to write arbitrary server files through a crafted tar upload. The KubernetesResource upload-outcomes endpoint passes request-body tar data to TarUtils.untar, which extracts entries without confining their paths to the workspace. A valid JobToken is required; successful traversal can overwrite files outside the intended extraction directory.

The record

CVE
CVE-2021-21251
Published
Jan 15, 2021
Updated
Aug 3, 2024
Vendor
OneDev Pty
Product
OneDev
Classifications
CWE-22, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 15, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 4.0.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

OneDev Pty · OneDevversion=< 4.0.3

Published CVSS scores

7.7GitHub CNACVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
8.8OSVCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1190Exploit Public-Facing Application

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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