CVE-2021-43097Public exploitNetwork attack vector

Authenticated code execution via FreeMarker template evaluation

Published Mar 28, 2022 · Updated Aug 4, 2024

SSTI in TemplateManageAction.java in diyhi bbs 5.3 allows remote authenticated users to execute arbitrary code through an edited template. The administrative template editor stores attacker-supplied HTML as a FreeMarker template, and the application evaluates that content when the site is accessed. Administrator access to the background-management interface is required, after which the injected code executes on the server when the affected template is rendered.

CVSS severity7.2
High
EPSS probability2.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SSTI in TemplateManageAction.java in diyhi bbs 5.3 allows remote authenticated users to execute arbitrary code through an edited template. The administrative template editor stores attacker-supplied HTML as a FreeMarker template, and the application evaluates that content when the site is accessed. Administrator access to the background-management interface is required, after which the injected code executes on the server when the affected template is rendered.

The record

CVE
CVE-2021-43097
Published
Mar 28, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-94, T1190
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Mar 28, 2022CVE 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 privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
T1190Exploit Public-Facing Application

Public exploit references

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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