CVE-2020-12873Network attack vector

Authenticated code execution via FreeMarker sandbox escape

Published Feb 19, 2021 · Updated Aug 4, 2024

Server-side template injection in Alfresco ECM before 6.2.1 allows remote authenticated users to execute code through FreeMarker templates. FreeMarker exposes an object graph that template editors can traverse to escape the sandbox and instantiate arbitrary Java objects. Template-editing privileges are required, and resulting Java code or system commands run with the privileges of the Alfresco service account.

CVSS severity8.8
High
EPSS probability1.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Server-side template injection in Alfresco ECM before 6.2.1 allows remote authenticated users to execute code through FreeMarker templates. FreeMarker exposes an object graph that template editors can traverse to escape the sandbox and instantiate arbitrary Java objects. Template-editing privileges are required, and resulting Java code or system commands run with the privileges of the Alfresco service account.

The record

CVE
CVE-2020-12873
Published
Feb 19, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-74, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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