Cyber Resilience

CVE-2021-44855

MediumPublic PoC

Published: 26 December 2022

Published
26 December 2022
Modified
14 April 2025
KEV Added
Patch
CVSS Score v3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0051 67.0th percentile
Risk Priority 11 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-44855 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Mediawiki Mediawiki. Its CVSS base score is 5.4 (Medium).

Operationally, ranked in the top 33.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. There is Blind Stored XSS via a URL to the Upload Image feature.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

mediawiki
mediawiki
1.37.0 · ≤ 1.35.5 · 1.36.0 — 1.36.3

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