0.0
NA
CVE-2026-31248
Docling's METS GBS Backend XML Entity Expansion Denial of Service
Description

Docling's METS GBS backend is vulnerable to XML Entity Expansion (XXE) attacks thru 2.61.0. The backend extracts and validates XML files from .tar.gz archives using etree.fromstring() without disabling entity resolution. An attacker can craft a malicious XML file with nested entity definitions (XML Bomb) and package it into a .tar.gz archive. When processed by Docling, the exponential expansion of entities during XML parsing leads to excessive resource consumption, resulting in a denial of service (DoS) condition on the system running the Docling parser.

INFO

Published Date :

May 11, 2026, 5:16 p.m.

Last Modified :

May 11, 2026, 5:16 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-31248 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Disable external entity resolution in XML parsers to prevent XXE attacks and resource exhaustion.
  • Update Docling's METS GBS backend to a secure version.
  • Configure the XML parser to disable external entity resolution.
  • Validate and sanitize all incoming XML files.
  • Limit resource allocation for XML parsing processes.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-31248.

URL Resource
https://github.com/docling-project/docling
https://www.notion.so/CVE-2026-31248-35d1e1393188818585b2ce3b9ce24686
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-31248 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-31248 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-31248 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-31248 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    May. 11, 2026

    Action Type Old Value New Value
    Added Description Docling's METS GBS backend is vulnerable to XML Entity Expansion (XXE) attacks thru 2.61.0. The backend extracts and validates XML files from .tar.gz archives using etree.fromstring() without disabling entity resolution. An attacker can craft a malicious XML file with nested entity definitions (XML Bomb) and package it into a .tar.gz archive. When processed by Docling, the exponential expansion of entities during XML parsing leads to excessive resource consumption, resulting in a denial of service (DoS) condition on the system running the Docling parser.
    Added Reference https://github.com/docling-project/docling
    Added Reference https://www.notion.so/CVE-2026-31248-35d1e1393188818585b2ce3b9ce24686
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.