JVM Application Logs Indicating Potential XXE via XML Parser Exceptions

Alerts on JVM XML parsing exception messages in application error logs that may indicate attempted XXE exploitation.

FreeReviewedSigma · High · v5
Product
jvm
Category
application
Author
Moti Harmats (SigmaHQ), DRL 1.1
Published
2023-02-11
Updated
2026-07-31
title: JVM Application Logs Indicating Potential XXE via XML Parser Exceptions
id: c4be6445-b934-42cd-8f0a-6410a1052228
status: test
description: This rule flags JVM application error logs containing XML parser exceptions that may indicate XML processing problems consistent with potential XXE exploitation attempts. Attackers can abuse insecure XML parsing to influence external entity resolution, so unexpected parsing exceptions are a useful signal when XML input is handled. Detection relies on application error log telemetry matching keywords such as SAXParseException and DOMException.
references:
  - https://rules.sonarsource.com/java/RSPEC-2755
  - https://owasp.org/www-community/vulnerabilities/XML_External_Entity_(XXE)_Processing
  - https://www.wix.engineering/post/threat-and-vulnerability-hunting-with-application-server-error-logs
  - https://github.com/SigmaHQ/sigma/blob/master/rules/application/jvm/java_xxe_exploitation_attempt.yml
author: Moti Harmats, Huntrule Team
date: 2023-02-11
tags:
  - attack.initial-access
  - attack.t1190
logsource:
  category: application
  product: jvm
  definition: "Requirements: application error logs must be collected (with LOG_LEVEL=ERROR and above)"
detection:
  keywords:
    - SAXParseException
    - DOMException
  condition: keywords
falsepositives:
  - If the application expects to work with XML there may be parsing issues that don't necessarily mean XXE.
level: high
license: DRL-1.1
related:
  - id: c4e06896-e27c-4583-95ac-91ce2279345d
    type: derived