CVE-2021-21251

ZipSlip Arbitrary File Upload

Description

OneDev is an all-in-one devops platform. In OneDev before version 4.0.3 there is a critical "zip slip" vulnerability. This issue may lead to arbitrary file write. The KubernetesResource REST endpoint untars user controlled data from the request body using TarUtils. TarUtils is a custom library method leveraging Apache Commons Compress. During the untar process, there are no checks in place to prevent an untarred file from traversing the file system and overriding an existing file. For a successful exploitation, the attacker requires a valid __JobToken__ which may not be possible to get without using any of the other reported vulnerabilities. But this should be considered a vulnerability in `io.onedev.commons.utils.TarUtils` since it lives in a different artifact and can affect other projects using it. This issue was addressed in 4.0.3 by validating paths in tar archive to only allow them to be in specified folder when extracted.

Category

7.7
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.71% Top 30%
Third-Party Advisory github.com
Affected: theonedev onedev
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-21251?
CVE-2021-21251 has been scored as a high severity vulnerability.
How to fix CVE-2021-21251?
To fix CVE-2021-21251, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21251 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21251 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21251?
CVE-2021-21251 affects theonedev onedev.
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