Summary
Docling: Unbounded table rowspan/colspan in HTML, JATS, ODS and BoxNote backends causes CPU/memory exhaustion
The HTML, JATS, ODS (OpenDocument spreadsheet) and BoxNote backends accept table rowspan / colspan values without an upper bound. A few bytes of input, such as <td rowspan="100000000">, make docling run loops proportional to the declared span and allocate a table grid of the declared size. The result is CPU and memory exhaustion.
Details
docling/backend/html_backend.py(_get_cell_spans) parses span attributes with no upper limit. The cell-filling loop then iteratesrow_span × col_spantimes.docling/backend/jats_backend.pyanddocling/backend/boxnote_backend.pyfill their tables the same way.- The OpenDocument spreadsheet path scans the declared span range.
- Export (for example
export_to_markdown()) materialises the full grid throughTableData.gridin docling-core.
document_timeout does not bound this. It is checked between pipeline stages, and these backends convert the whole document in a single call. max_file_size and max_num_pages do not help because the payload is tiny.
Measured on 2.130.0: a 54-byte HTML file with rowspan="1e8" takes about 4.4 s of CPU, and the time grows linearly with the value. A 52-byte file with colspan="3000000" takes about 23 s and reaches 4.5 GB peak memory during Markdown export.
Proof of concept
<table><tr><td colspan="3000000">x</td></tr></table>
from docling.document_converter import DocumentConverter
DocumentConverter().convert("span.html").document.export_to_markdown()
Workarounds
Upgrade to 2.131.0. For older versions:
Run conversions of untrusted documents in a separate process with memory and CPU-time limits, or restrict allowed_formats to formats that are not affected.
Impact
Denial of service of the converting process from a very small input document. Confidentiality and integrity are not affected.
Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.
CVE-2026-105749 has a CVSS score of 6.5 (Medium). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.131.0); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Fixed in docling 2.131.0 by #4414. Table spans are clamped to the HTML limits (colspan 1000, rowspan 65534) and to the actual size of the table in the HTML, JATS, BoxNote and OpenDocument spreadsheet backends, so conversion time and memory grow with the real table only.
Frequently Asked Questions
- What is CVE-2026-105749? CVE-2026-105749 is a medium-severity uncontrolled resource consumption vulnerability in docling (pip), affecting versions >= 2.0.0, < 2.131.0. It is fixed in 2.131.0. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.
- How severe is CVE-2026-105749? CVE-2026-105749 has a CVSS score of 6.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which packages are affected by CVE-2026-105749?
docling(pip) (versions >= 2.0.0, < 2.131.0)docling-slim(pip) (versions >= 2.92.0, < 2.131.0)
- Is there a fix for CVE-2026-105749? Yes. CVE-2026-105749 is fixed in 2.131.0. Upgrade to this version or later.
- Is CVE-2026-105749 exploitable, and should I be worried? Whether CVE-2026-105749 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-105749 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-105749?
- Upgrade
doclingto 2.131.0 or later - Upgrade
docling-slimto 2.131.0 or later
- Upgrade