Vulnerability · Published Sep 30, 2020 · Assigned by mitre
CVE-2020-21523
Critical 9.8
In plain English
A critical-severity security flaw in the affected software. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 2.6% (higher than 85% of all known vulnerabilities).
Severity (CVSS NVD)9.8Critical
Exploit odds (30 days)2.6%top 14.7% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
A Server-Side Freemarker template injection vulnerability in halo CMS v1.1.3 In the Edit Theme File function. The ftl file can be edited. This is the Freemarker template file. This file can cause arbitrary code execution when it is rendered in the background. exp: <#assign test="freemarker.template.utility.Execute"?new()> ${test("touch /tmp/freemarkerPwned")}
Affected products (as reported)
References
- https://github.com/halo-dev/halo/issues/419 x_refsource_MISC