CVE-2021-43787

Public Exploit
XSS via prototype pollution

Description

Nodebb is an open source Node.js based forum software. In affected versions a prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report. The vulnerability has been patched as of v1.18.5. Users are advised to upgrade as soon as possible.

Category

9.0
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.37%
Third-Party Advisory sonarsource.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: NodeBB NodeBB
Published at:
Updated at:

References

Link Tags
https://github.com/NodeBB/NodeBB/security/advisories/GHSA-wx69-rvg3-x7fc third party advisory patch
https://github.com/NodeBB/NodeBB/commit/1783f918bc19568f421473824461ff2ed7755e4c third party advisory patch
https://github.com/NodeBB/NodeBB/releases/tag/v1.18.5 release notes third party advisory patch
https://blog.sonarsource.com/nodebb-remote-code-execution-with-one-shot/ third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-43787?
CVE-2021-43787 has been scored as a critical severity vulnerability.
How to fix CVE-2021-43787?
To fix CVE-2021-43787, 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-2021-43787 being actively exploited in the wild?
It is possible that CVE-2021-43787 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43787?
CVE-2021-43787 affects NodeBB NodeBB.
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