CVE-2020-21524
CVSS v3
9.1
CRITICAL
EPSS Score
1.5 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
There is a XML external entity (XXE) vulnerability in halo v1.1.3, The function of importing other blogs in the background(/api/admin/migrations/wordpress) needs to parse the xml file, but it is not used for security defense, This vulnerability can detect the intranet, read files, enable ddos attacks, etc. exp:https://github.com/halo-dev/halo/issues/423
Technical details
- Published
- 2020-09-30
Frequently asked questions
What is CVE-2020-21524?
There is a XML external entity (XXE) vulnerability in halo v1.1.3, The function of importing other blogs in the background(/api/admin/migrations/wordpress) needs to parse the xml file, but it is not used for security defense, This vulnerability can detect the intranet, read files, enable ddos attacks, etc. exp:https://github.com/halo-dev/halo/issues/423
Is CVE-2020-21524 actively exploited?
Active exploitation of CVE-2020-21524 has not been confirmed. Its EPSS score was 1.5% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2020-21524?
CVE-2020-21524 has a CVSS v3 base score of 9.1 (CRITICAL severity).
Is CVE-2020-21524 affecting your environment?
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