Docling: Unsafe XML Entity Expansion in USPTO Patent Backend

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-44020: 0.60% estimated exploitation activity in the next 30 days; percentile 48.80 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact The USPTO patent XML parser used the standard xml.sax.parseString() without protection against XML External Entity (XXE) attacks. An attacker could craft malicious USPTO patent XML files with external entity references that could: - Read arbitrary files from the server filesystem - Perform Server-Side Request Forgery (SSRF) attacks - Cause denial of service through entity expansion (Billion Laughs attack) The vulnerability affects three USPTO patent format parsers: ICE (v4.x), Grant v2.5, and Application v1.x. Patches Fixed in version 2.74.0. The parser now uses defusedxml.sax.makeparser() with secure configuration that blocks external entity resolution (featureexternalges=False, featureexternalpes=False) while allowing DTD declarations required by USPTO files. This prevents XXE attacks while maintaining compatibility with the USPTO XML format. Workarounds Avoid processing USPTO patent XML files from untrusted sources. Implement resource limits (memory, CPU time) when…

Published by the source

3 Jun 2026, 21:14 UTC

Last modified by the source

28 Aug 2026, 18:45 UTC

Source last checked

26 Oct 2026, 13:50 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-m88r-rg27-5xfg

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-m88r-rg27-5xfg

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# Patch Next advisory brief: CVE-2026-44020

Advisory: Docling: Unsafe XML Entity Expansion in USPTO Patent Backend
IDs: CVE-2026-44020, GHSA-m88r-rg27-5xfg
Record: https://patchnext.com/advisories/cve-2026-44020 (revision 2, source checked 26 Oct 2026, 13:50 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: docling 2.74.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI docling: affected >= 2.13.0, < 2.74.0; fixed in 2.74.0

## Suggested inspection (read-only)
- `python -m pip show docling`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on docling.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-m88r-rg27-5xfg (OSV record GHSA-m88r-rg27-5xfg lists affected ranges: PyPI docling >=2.13.0 <2.74.0 (fixed))
- Verified: https://github.com/advisories/GHSA-m88r-rg27-5xfg (GitHub-reviewed advisory GHSA-m88r-rg27-5xfg lists affected ranges: PyPI docling >=2.13.0 <2.74.0)

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