CVE-2020-21523
9.8
CRITICAL · CVSS 3.1 · EPSS 2.6% (pctl 85)
In your normal cycle
Critical by CVSS (9.8), but no sign of active exploitation.
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")}
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 2.59% — more likely to be exploited than 85% of all CVEs |
| Weakness | CWE-74 |
| On CISA KEV | no |
| Public exploit | none known |
| Published | 2020-09-30 |
| Last modified | 2026-06-17 |
Affected (1)
| Vendor | Product |
|---|---|
| halo | halo |
→ the Explorer · watch your stack · NVD