# CVE-2026-123198: LMFDB before commit 01829bd Unauthenticated Server-Side Template Injection via /knowledge/render/<ID>

Status: published. Published: 2026-11-05. Updated: 2026-11-05.

LMFDB before commit 01829bd contains a server-side template injection vulnerability in the render_knowl function that allows unauthenticated attackers to inject Jinja expressions via request parameters. Attackers can supply crafted query-string values or 'content' data to /knowledge/render/<ID> to reach Python builtins and execute operating system commands as the web application account.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/LMFDB/lmfdb/pull/7231
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/LMFDB/lmfdb/commit/01829bd09b692c720aad30c952758a20630573d4

## Affected products and versions

- LMFDB / LMFDB (lmfdb/lmfdb): ≥ 0; < 01829bd09b692c720aad30c952758a20630573d4 (affected, git). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 9.3 (critical); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 9.8 (critical); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: exploitation poc; automatable yes; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-1336

## Exploit evidence

- exploit: https://github.com/LMFDB/lmfdb/security/advisories/GHSA-6jw3-pmcx-2xww (ADP: CISA-ADP)

## References

- https://github.com/LMFDB/lmfdb/security/advisories/GHSA-6jw3-pmcx-2xww (CNA: VulnCheck; vendor-advisory)

- https://github.com/LMFDB/lmfdb/pull/7231 (CNA: VulnCheck; patch, issue-tracking)

- https://github.com/LMFDB/lmfdb/commit/01829bd09b692c720aad30c952758a20630573d4 (CNA: VulnCheck; patch)

- https://github.com/LMFDB/lmfdb/blob/c6e5bac205aa12de9edf584a06328fefa81de0de/lmfdb/knowledge/main.py#L747 (CNA: VulnCheck; technical-description)

- https://www.vulncheck.com/advisories/lmfdb-before-commit-01829bd-unauthenticated-server-side-template-injection-via-knowledge-render-id (CNA: VulnCheck; third-party-advisory)

- https://github.com/LMFDB/lmfdb/security/advisories/GHSA-6jw3-pmcx-2xww (ADP: CISA-ADP; exploit)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-123198; retrieved 2026-11-05; source updated 2026-11-05

Revision: 54ac621eca2041a67ee96399b8cd9066ee27dad32e426437192c9e916b37836e

Canonical: https://y2.dev/cve/CVE-2026-123198

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

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