XSS in Nodebb

CVE-2021-43787

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.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.013 (69.6th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 70th percentile — 69.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-43787: held from 0.013 to 0.013.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: +0.000

Affected products

  • Nodebb — versions >= 1.15.5, < 1.18.5

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-43787?
CVE-2021-43787 is a critical-severity vulnerability in Nodebb, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2021-11-29.
How severe is CVE-2021-43787?
Critical severity. CVSS v3 base score is 9.0 out of 10.