CVE Vulnerability

CVE-2021-21249

OneDev is an all-in-one devops platform. In OneDev before version 4.0.3, there is an issue involving YAML parsing which can lead to post-auth remote code execution. In order to parse and process YAML files, OneDev uses SnakeYaml which by default (when not using `SafeConstructor`) allows the instantiation of arbitrary classes. We can leverage that to run arbitrary code by instantiating classes such as `javax.script.ScriptEngineManager` and using `URLClassLoader` to load the script engine provider, resulting in the instantiation of a user controlled class. For a full example refer to the referenced GHSA. This issue was addressed in 4.0.3 by only allowing certain known classes to be deserialized

6.5 /10

CVSS v2.0 :

V3 Legend

Vector :

Exploitability : 8 / Impact : 6.4

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

Scope

8.8 /10

CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://github.com/theonedev/onedev/security/advisories/GHSA-7xhq-m2q9-6hpm Third Party Advisory
https://github.com/theonedev/onedev/commit/d6fc4212b1ac1e9bbe3ce444e95f9af1e3ab8b66 Patch Third Party Advisory
Configurations

Configuration 1

cpe:2.3:a:onedev_project:onedev:*:*:*:*:*:*:*:*
Information

Published : 2021-01-15 09:15

Updated : 2022-04-26 04:13

NVD link : CVE-2021-21249

Mitre link : CVE-2021-21249

Products Affected
No products.
CWE
CWE-502

Deserialization of Untrusted Data