Docling up to 2.61.0 XML Parser etree.fromstring xml external entity reference

Summaryinfo

A vulnerability was found in Docling up to 2.61.0. It has been declared as problematic. This issue affects the function etree.fromstring of the component XML Parser. The manipulation results in xml external entity reference. This vulnerability was named CVE-2026-31248. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability classified as critical has been found in Docling up to 2.61.0. Affected is the function etree.fromstring of the component XML Parser. The manipulation with an unknown input leads to a xml external entity reference vulnerability. CWE is classifying the issue as CWE-611. The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-31248 since 03/09/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 05/11/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Name

• Docling

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27
• 2.28
• 2.29
• 2.30
• 2.31
• 2.32
• 2.33
• 2.34
• 2.35
• 2.36
• 2.37
• 2.38
• 2.39
• 2.40
• 2.41
• 2.42
• 2.43
• 2.44
• 2.45
• 2.46
• 2.47
• 2.48
• 2.49
• 2.50
• 2.51
• 2.52
• 2.53
• 2.54
• 2.55
• 2.56
• 2.57
• 2.58
• 2.59
• 2.60
• 2.61.0

CPE 2.3info

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CPE 2.2info

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Entryinfo

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