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.
docling accepts serialized DoclingDocument JSON as an input format (InputFormat.JSON_DOCLING, enabled by default). A crafted JSON file can set a picture's image uri to a local file path. When the converted document is exported with embedded images (ImageRefMode.EMBEDDED, the CLI default for Markdown and HTML), the referenced file is read and embedded as base64 in the output.
HTMLBackendOptions.headers is documented for passing authentication headers (API keys, bearer tokens) when fetching remote images. docling sends these headers on every remote image request, to whichever host the document names. An untrusted document that references an attacker-controlled image URL receives the caller's credentials.
allow_external_plugins=False (the default, and the CLI default) is meant to restrict docling to its own model plugins. However, docling's plugin factories call pluggy's load_setuptools_entrypoints(), which imports every module registered under docling's plugin entry-point group. Only afterwards does docling filter out modules outside the docling. namespace. Import-time code in any installed third-party plugin therefore runs even though external plugins are disabled.
When remote fetching is enabled (enable_remote_fetch=True, together with fetch_images=True or HTML render_page=True), docling's protection against requests to private and loopback addresses can be bypassed. The URL check resolves the host name once, to a single IPv4 address. The HTTP request then resolves it again. A name that returns a public A record together with an internal AAAA record, or one that changes its answer between the two lookups (DNS rebinding), …
When the LaTeX backend is configured to render TikZ pictures with the Tectonic engine (LatexBackendOptions(tikz_engine="tectonic")), the TikZ body and the document preamble from the input file are compiled by Tectonic without any restriction on TeX's file primitives. A crafted .tex file can read files the process can read and write files at paths the process can write. If the caller also sets tikz_engine_allow_shell_escape=True, the document can run shell commands through …
When docling detects the input format of a gzip-compressed tar archive (METS-GBS), and later when the METS-GBS backend opens it, it calls tarfile.TarFile.getmembers(). That builds the full member list in memory before the max_member_count limit is checked. A small archive with a very large number of empty members therefore makes docling allocate memory in proportion to the member count, and the limit has no effect.
When the HTML backend renders pages in a headless browser (HTMLBackendOptions(render_page=True)), the enable_local_fetch option is not enforced. A crafted HTML file can embed an arbitrary local file (for example with <iframe src="file:///…">), and that file's contents appear in the page image attached to the returned DoclingDocument.
The ODF backend resolves the xlink:href of a draw:image element as a filesystem path whenever the referenced part is not found inside the document archive. The value comes straight from content.xml, so it is document content, and it is used with no scheme check, no confinement to the extraction directory, and without consulting the enable_local_fetch / enable_remote_fetch controls that the other backends use for exactly this decision. Converting a crafted …
In versions < 2.91.0, The EasyOCR model download functionality extracted ZIP archives without validating member paths, enabling Zip Slip attacks. If an attacker could compromise the model download source (via supply chain attack, DNS spoofing, or MITM), they could write arbitrary files to any location writable by the process, potentially achieving: Remote code execution by overwriting Python files or system binaries Persistent backdoors by modifying startup scripts or SSH keys …
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.
The HTML backend did not perform sufficient validation during resource handling: Accepted file:// URIs enabling local file system access when enable_local_fetch=True Path resolution allowed traversal outside intended directories via ../ sequences and absolute paths Did not block internal network resources under enable_remote_fetch=True HTTP redirects were not validated, potentially redirecting to unintended schemes No resource limits for remote image downloads and data: URIs
In versions >= 2.82.0, < 2.91.0, if the HTML backend was explicitly configured for rendering (rendering option by default deactivated), then the Playwright-based rendering feature could allow JavaScript execution and unrestricted network access when processing untrusted HTML documents. An attacker could craft malicious HTML that executes arbitrary JavaScript in the rendering context or makes unauthorized network requests to internal services, potentially leading to SSRF attacks, data exfiltration, or remote code …
The METS-GBS backend's XML parsing and the input document format detection lacked security controls, enabling: XML External Entity (XXE) attacks to read local files or cause denial of service Decompression bombs (zip bombs) to exhaust memory and disk space Unbounded archive extraction consuming system resources An attacker could craft malicious METS-GBS archives that, when processed, could read sensitive files, exhaust system resources, or cause application crashes.
The LaTeX backend's handling of \includegraphics, \input, and \include commands lacked path containment validation. Attackers could craft malicious LaTeX documents with path traversal sequences (e.g., ../../../etc/passwd) to: Read arbitrary files from the file system accessible to the process Include sensitive files in the converted document output Potentially access configuration files, credentials, or other sensitive data
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 …
Docling's JATS XML backend is vulnerable to XML Entity Expansion (XXE) attacks thru 2.61.0. The backend uses etree.parse() to parse XML files without disabling entity resolution. An attacker can craft a malicious XML file containing a nested entity expansion payload (XML Bomb). When processed by Docling, the exponential expansion of entities leads to excessive resource consumption, resulting in a denial of service (DoS) condition on the system running the Docling …