XSS in Flarum Core
CVE-2021-32671
Flarum is a forum software for building communities. Flarum's translation system allowed for string inputs to be converted into HTML DOM nodes when rendered. This change was made after v0.1.0-beta.16 (our last beta before v1.0.0) and was n…
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.397 (98.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.
Affected products
- Flarum Core — versions >= 1.0.0, < 1.0.2
- Flarum — versions 1.0.0, 1.0.1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
- security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC)
- security-advisories@github.com (Product, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2021-32671?
- CVE-2021-32671 is a critical-severity vulnerability in Flarum Core, classified under Cross-site Scripting. CVSS score: 10.0/10. Published 2021-06-07.
- How severe is CVE-2021-32671?
- Critical severity. CVSS v3 base score is 10.0 out of 10.
- Is CVE-2021-32671 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.