CVE-2021-21242
CriticalIn OneDev before version 4.0.3, there is a critical vulnerability which can lead to pre-auth remote code execution.
Published Jan 15, 2021 · Updated Oct 9, 2026 · Also known as GHSA-5q3q-f373-2jv8
Key Facts
Patch immediately- CVE-2021-21242 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Onedev (Onedev Project).
- It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
- EPSS estimates a 74% probability of exploitation in the next 30 days.
- Fixed versions are available, including Onedev 4.0.3.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
74%
Higher than 99.4% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
None known
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Description
OneDev is an all-in-one devops platform. In OneDev before version 4.0.3, there is a critical vulnerability which can lead to pre-auth remote code execution. AttachmentUploadServlet deserializes untrusted data from the Attachment-Support header. This Servlet does not enforce any authentication or authorization checks. This issue may lead to pre-auth remote code execution. This issue was fixed in 4.0.3 by removing AttachmentUploadServlet and not using deserialization
Affected Products
2 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| OnedevOnedev Project | >= < 4.0.3 | 4.0.3 |
Patched Releases
Onedev
4.0.3
Timeline
Publicly disclosed
Jan 15, 2021
Last updated
Oct 9, 2026
Weakness Type
- CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
- CWE-502 Deserialization of Untrusted Data
References
FAQ
Common Questions.
OneDev is an all-in-one devops platform.
Affected: Onedev (Onedev Project) versions >= < 4.0.3. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Onedev 4.0.3.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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