CVE-2026-31247: High severity Docling Docling JATS XML backend vulnerability
Docling's JATS XML backend is vulnerable to XML Entity Expansion (XXE) attacks thru 2.61.0. The backend uses etree.parse() to parse XML files without disabling entity resolution. An attacker can craft a malicious XML file containing a nested entity expansion payload (XML Bomb). When processed by Docling, the exponential expansion of entities leads to excessive resource consumption, resulting in a denial of service (DoS) condition on the system running the Docling parser.
Affected Software
Event History
Frequently Asked Questions
Who is exposed to this issue?
Systems that process attacker-controlled or otherwise untrusted JATS XML files with Docling's JATS XML backend are exposed. The issue can be triggered remotely through malicious XML input and does not require authentication or user interaction.
What does an attacker need to exploit it?
An attacker needs to provide a crafted JATS XML document containing nested entity expansions. Processing that document with the affected backend can consume excessive system resources and cause a denial-of-service condition.
Which Docling versions are affected?
The issue affects the Docling JATS XML backend through version 2.61.0. The provided information does not identify a fixed version.
What should teams do if they cannot patch immediately?
Do not process untrusted JATS XML files with the affected backend until a fix is available. Restrict XML inputs to trusted sources to reduce the opportunity for an attacker to submit an entity-expansion payload.