What’s Vulnerable › Vulnerabilities

CVE-2021-21242: Pre-Auth Unsafe Deserialization on AttachmentUploadServet

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 74.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-01-15 · updated 2026-06-17
• Weakness: CWE-74

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

• theonedev onedev: before 4.0.3 — fixed in 4.0.3

How to fix

Upgrade to a fixed version: theonedev onedev 4.0.3. Check the vendor advisory for mitigations.

References

• https://github.com/theonedev/onedev/commit/f864053176c08f59ef2d97fea192ceca46a4d9be
• https://github.com/theonedev/onedev/security/advisories/GHSA-5q3q-f373-2jv8
• https://github.com/theonedev/onedev/commit/f864053176c08f59ef2d97fea192ceca46a4d9be
• https://github.com/theonedev/onedev/security/advisories/GHSA-5q3q-f373-2jv8

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