local-deep-research is Vulnerable to HTML Injection via Unescaped User Input in PDF Export (pdf_service.py:_markdown_to_html)

Exploitation

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

CVSS

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

EPSS

• CVE-2026-43979: 0.33% estimated exploitation activity in the next 30 days; percentile 26.34 (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 PDFService.markdowntohtml() constructs an HTML document by interpolating user-controlled values — specifically title (sourced from research.title or research.query) and metadata key-value pairs — directly into an f-string without any HTML escaping. An authenticated attacker can craft a research query containing HTML special characters to inject arbitrary HTML tags into the document processed by WeasyPrint during PDF export. This injection can be chained to trigger a Server-Side Request Forgery (SSRF), bypassing the application's existing SSRF defenses in ssrfvalidator.py. --- Details Vulnerable code: src/localdeepresearch/web/services/pdfservice.py, lines 171–176 Data flow trace: research.query is a string submitted by the user via POST /api/startresearch, stored as-is in the database, and retrieved without any sanitization. When the user triggers POST /api/v1/research/<researchid/export/pdf, this value is embedded unescaped into the HTML document processed by WeasyPrint.…

Published by the source

11 May 2026, 19:40 UTC

Last modified by the source

13 Jul 2026, 16:42 UTC

Source last checked

26 Oct 2026, 13:45 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-fj2m-qvh9-jq4q

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-fj2m-qvh9-jq4q

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# Patch Next advisory brief: CVE-2026-43979

Advisory: local-deep-research is Vulnerable to HTML Injection via Unescaped User Input in PDF Export (`pdf_service.py:_markdown_to_html`)
IDs: CVE-2026-43979, GHSA-fj2m-qvh9-jq4q
Record: https://patchnext.com/advisories/cve-2026-43979 (revision 2, source checked 26 Oct 2026, 13:45 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: local-deep-research 1.6.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI local-deep-research: affected < 1.6.0; fixed in 1.6.0

## Suggested inspection (read-only)
- `python -m pip show local-deep-research`: 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 local-deep-research.
- 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-fj2m-qvh9-jq4q (OSV record GHSA-fj2m-qvh9-jq4q lists affected ranges: PyPI local-deep-research >=0 <1.6.0 (fixed))
- Verified: https://github.com/advisories/GHSA-fj2m-qvh9-jq4q (GitHub-reviewed advisory GHSA-fj2m-qvh9-jq4q lists affected ranges: PyPI local-deep-research >=0 <1.6.0)

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