CVE-2021-20815
Published: 26 August 2021
Summary
CVE-2021-20815 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Sixapart Movable Type. Its CVSS base score is 6.1 (Medium).
Operationally, ranked in the top 42.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-8227
Vulnerability details
Cross-site scripting vulnerability in Edit Boilerplate screen of Movable Type (Movable Type 7 r.4903 and earlier (Movable Type 7 Series), Movable Type 6.8.0 and earlier (Movable Type 6 Series), Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7…
more
Series), Movable Type Premium 1.44 and earlier, and Movable Type Premium Advanced 1.44 and earlier) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.
Validates web inputs to reject script-related content that could produce XSS.
Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.