What is the CVSS score of CVE-2020-21524?

CVE-2020-21524 has a CVSS 3.1 base score of 9.1 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H. EPSS exploitation probability: 1.5%.

Is there a public PoC exploit available for CVE-2020-21524?

Yes, a public proof-of-concept exploit is available for CVE-2020-21524. Prioritise patching immediately. EPSS: 1.5%.

Halo CVE-2020-21524

CRITICAL

Improper Restriction of XML External Entity Reference (CWE-611)

2020-09-30 cve@mitre.org

WordPress XXE Halo

9.1

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.1 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Lifecycle Timeline

CVE Published

Sep 30, 2020 - 18:15 nvd

CRITICAL 9.1

DescriptionNVD

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

AnalysisAI

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. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

Technical ContextAI

This vulnerability is classified as XML External Entity (XXE) (CWE-611), which allows attackers to read arbitrary files or perform SSRF through XML processing. 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 Affected products include: Halo.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Disable external entity processing in XML parsers, use JSON instead of XML where possible.