CVE-2021-41110

Public Exploit
CWL Viewer: deserialization of untrusted data can lead to complete takeover by an attacker

Description

cwlviewer is a web application to view and share Common Workflow Language workflows. Versions prior to 1.3.1 contain a Deserialization of Untrusted Data vulnerability. Commit number f6066f09edb70033a2ce80200e9fa9e70a5c29de (dated 2021-09-30) contains a patch. There are no available workarounds aside from installing the patch. The SnakeYaml constructor, by default, allows any data to be parsed. To fix the issue the object needs to be created with a `SafeConstructor` object, as seen in the patch.

Category

9.1
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.61%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory fatalerrors.org
Affected: common-workflow-language cwlviewer
Published at:
Updated at:

References

Link Tags
https://github.com/common-workflow-language/cwlviewer/security/advisories/GHSA-7g7j-f5g3-fqp7 third party advisory patch
https://github.com/common-workflow-language/cwlviewer/commit/f6066f09edb70033a2ce80200e9fa9e70a5c29de third party advisory patch
https://www.fatalerrors.org/a/analysis-of-the-snakeyaml-deserialization-in-java-security.html third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-41110?
CVE-2021-41110 has been scored as a critical severity vulnerability.
How to fix CVE-2021-41110?
To fix CVE-2021-41110, 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-2021-41110 being actively exploited in the wild?
It is possible that CVE-2021-41110 is being exploited or will be exploited in a near future based on public information. 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-2021-41110?
CVE-2021-41110 affects common-workflow-language cwlviewer.
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