Cyber Resilience

CVE-2021-47963

MediumPublic PoC

Published: 15 May 2026

Published
15 May 2026
Modified
18 May 2026
KEV Added
Patch
CVSS Score v4 5.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0003 8.1th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-47963 is a medium-severity Cross-site Scripting (CWE-79) vulnerability. Its CVSS base score is 5.1 (Medium).

Operationally, ranked at the 8.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Anote 1.0 contains a persistent cross-site scripting vulnerability that allows attackers to execute arbitrary code by injecting malicious payloads into markdown files stored within the application. Attackers can craft malicious markdown files with embedded JavaScript that executes system commands when…

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opened, enabling remote code execution on the victim's computer.

CWE(s)

Related Threats

CVEs Like This One

CVE-2024-13574Shared CWE-79
CVE-2021-47873Shared CWE-79
CVE-2025-23578Shared CWE-79
CVE-2026-3231Shared CWE-79
CVE-2025-23481Shared CWE-79
CVE-2025-23593Shared CWE-79
CVE-2026-7052Shared CWE-79
CVE-2025-25203Shared CWE-79
CVE-2025-27279Shared CWE-79
CVE-2018-25248Shared CWE-79

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.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References