CVE-2021-23262Network attack vector

Server code execution via YAML class loading

Published Dec 2, 2021 · Updated Sep 16, 2024

Remote code execution in CrafterCMS 3.1 before 3.1.13 allows remote authenticated users to load Java classes through crafted YAML. The main YAML configuration is deserialized without enforcing the intended class-loading restriction, so administrator-controlled content selects a Java class. Administrator privileges and user interaction are required; successful exploitation executes server-side code, while the CNA assessment reports availability impact only.

CVSS severity4.2
Medium
EPSS probability0.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Remote code execution in CrafterCMS 3.1 before 3.1.13 allows remote authenticated users to load Java classes through crafted YAML. The main YAML configuration is deserialized without enforcing the intended class-loading restriction, so administrator-controlled content selects a Java class. Administrator privileges and user interaction are required; successful exploitation executes server-side code, while the CNA assessment reports availability impact only.

The record

CVE
CVE-2021-23262
Published
Dec 2, 2021
Updated
Sep 16, 2024
Vendor
Crafter Software Corporation
Product
CrafterCMS
Classifications
CWE-913
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Dec 2, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.1 <3.1.13

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Crafter Software Corporation · CrafterCMSversion=3.1 <3.1.13

Published CVSS scores

7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
4.2Crafter CMSCVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P

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 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 exploitUnconfirmed

Weakness, pattern, technique

CWE-913Improper Control of Dynamically-Managed Code Resources

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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