Home/CVE/MyBB before 1.8.28 allows stored XSS because the displayed Template Name value in the Admin CP's theme management is not
CVE

CVE-2021-41866

MyBB before 1.8.28 allows stored XSS because the displayed Template Name value in the Admin CP's theme management is not

MyBB before 1.8.28 allows stored XSS because the displayed Template Name value in the Admin CP's theme management is not escaped properly.

MEDIUM · CVSS 5.4 EPSS 0.00281
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
▤

Affected Products & Versions

1
mybb< 1.8.28
▣

Scoring & Timeline

5.4
MEDIUM · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD26 Oct 2021 · 10:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/mybb/mybb/security/advisories/Third Party Advisory
https://github.com/mybb/mybb/security/advisories/GHSA-gxhv-r3m5-6qv7PatchThird Party Advisory
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