Docling has SSRF guard bypass in remote resource fetching (DNS rebinding / multi-record resolution; no IP validation in HTML render mode)

Exploitation

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

CVSS

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

EPSS

• CVE-2026-105743: 0.20% estimated exploitation activity in the next 30 days; percentile 10.07 (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.

Summary When remote fetching is enabled (enableremotefetch=True, together with fetchimages=True or HTML renderpage=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), reaches internal addresses. - The check and the HTTP request parse the URL differently. With a backslash in the authority, such as http://127.0.0.1:8080\@1.1.1.1/x.png, the check validates 1.1.1.1 while the HTTP client connects to 127.0.0.1:8080. - In HTML browser-rendering mode (renderpage=True), requests made by the page are allowed for any http(s) URL without an IP check. Details - validateurlsafety in docling/backend/utils/imageresourceloader.py calls socket.gethostbyname(), which returns one IPv4 address. It checks…

Published by the source

7 Oct 2026, 20:42 UTC

Last modified by the source

15 Oct 2026, 14:56 UTC

Source last checked

26 Oct 2026, 13:55 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-pc36-qwjq-x68c

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-pc36-qwjq-x68c

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-pc36-qwjq-x68c

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# Patch Next advisory brief: CVE-2026-105743

Advisory: Docling has SSRF guard bypass in remote resource fetching (DNS rebinding / multi-record resolution; no IP validation in HTML render mode)
IDs: CVE-2026-105743, GHSA-pc36-qwjq-x68c
Record: https://patchnext.com/advisories/cve-2026-105743 (revision 3, source checked 26 Oct 2026, 13:55 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: docling-slim 2.132.0; docling 2.132.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI docling-slim: affected >= 2.92.0, < 2.132.0; fixed in 2.132.0
- PyPI docling: affected >= 2.91.0, < 2.132.0; fixed in 2.132.0

## Suggested inspection (read-only)
- `python -m pip show docling-slim`: prints the installed version. Run with the environment that serves production active.
- `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-slim, 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://github.com/advisories/GHSA-pc36-qwjq-x68c (GitHub-reviewed advisory GHSA-pc36-qwjq-x68c lists affected ranges: PyPI docling >=2.91.0 =2.92.0 <2.132.0)
- Verified: https://osv.dev/vulnerability/GHSA-pc36-qwjq-x68c (OSV record GHSA-pc36-qwjq-x68c lists affected ranges: PyPI docling >=2.91.0 =2.92.0 <2.132.0 (fixed))

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