CVE-2026-52439Network attack vector

Remote code execution via unsafe expression reflection

Published Jul 23, 2026 · Updated Jul 23, 2026

Expression language injection in xiandafu Beetl 3.20.2 allows remote attackers to execute arbitrary code through a crafted template. Beetl evaluates untrusted template expressions through type.new and property reflection without neutralizing elements that trigger object construction and member access. Exploitation requires an application to render attacker-controlled templates, and resulting code runs with the hosting JVM's privileges.

CVSS severity9.8
Critical
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Expression language injection in xiandafu Beetl 3.20.2 allows remote attackers to execute arbitrary code through a crafted template. Beetl evaluates untrusted template expressions through type.new and property reflection without neutralizing elements that trigger object construction and member access. Exploitation requires an application to render attacker-controlled templates, and resulting code runs with the hosting JVM's privileges.

The record

CVE
CVE-2026-52439
Published
Jul 23, 2026
Updated
Jul 23, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-917, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 23, 2026Record 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 privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-917Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection')
T1190Exploit Public-Facing Application

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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