Home/CVE/An issue was discovered in Joomla! before 3.9.15. Inadequate escaping of usernames allows XSS attacks in com_actionlogs.
CVE

CVE-2020-8421

An issue was discovered in Joomla! before 3.9.15. Inadequate escaping of usernames allows XSS attacks in com_actionlogs.

An issue was discovered in Joomla! before 3.9.15. Inadequate escaping of usernames allows XSS attacks in com_actionlogs.

MEDIUM · CVSS 6.1 EPSS 0.02143
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
joomla joomla\!>= 3.9.0 and < 3.9.14
▣

Scoring & Timeline

6.1
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 NVD28 Jan 2020 · 09:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://developer.joomla.org/security-centre/800-20200103-core-xss-in-com-actionlogsVendor Advisory
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