CVE-2026-31248 Docling's METS GBS backend is vulnerable to XML Entity Expansion (XXE) attacks
An attacker can cause denial of service in Docling by submitting a crafted archive containing malicious XML with nested entities.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-31248?
CVE-2026-31248 is a high-severity vulnerability in n/a, published on 11 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-776
Which versions are affected by CVE-2026-31248?
3 open source packages ship an affected version, including docling.
| Package | Affected | Fixed in |
|---|---|---|
docling PyPI | All versions to 2.61.0 | None |
docling PyPI | All versions to 2.61.0 | None |
docling PyPI | All versions to 2.61.0 | None |
How do I fix CVE-2026-31248?
No fix has been published for CVE-2026-31248 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-31248 being exploited?
There is no known exploitation of CVE-2026-31248 in the wild and no public exploit code.
Sources
Also known as GHSA-9f4q-q82q-4359, PYSEC-2026-2454.