Sign in Sign up
JA · EN · FR
SecPulse
Categories
CVE-2026-71417 high CVSS 7.3

Vulnerability in lemur (CVE-2026-71417)

Summary

Vulnerability in lemur (CVE-2026-71417). Risk of unauthorized operations or information disclosure. Exploitable via PUT /api/1/certificates/. Mitigation: upgrade to 1.9.3 or later.

Original description

The description as published by the source.

Summary

Repo under test: https://github.com/Netflix/lemur

PUT /api/1/certificates//revoke authorizes the caller against the Lemur database row (creator == current user, or CertificatePermission over the row's roles) rather than the underlying CA-side certificate identity. Separately, POST /api/1/certificates/upload lets any user passing StrictRolePermission create a new Certificate row while freely supplying body, authority (resolved by id/name with no AuthorityPermission check) and external_id; there is no uniqueness constraint on body, serial, or external_id.

An attacker can therefore read a target certificate's public body, authority.id, and external_id via GET /certificates/, upload a duplicate row, and revoke that duplicate. The creator-bypass skips CertificatePermission, the empty-endpoints check passes because the duplicate has none, and service.revoke() then revokes at the CA using the attacker-supplied body (ACME) or external_id (DigiCert/Entrust/Google CA/CFSSL) under the authority's stored CA credentials — revoking the real production certificate.

Affected route

POST /api/1/certificates/upload → PUT /api/1/certificates//revoke

Affected code

Source: GitHub Security Advisories (Global) NVD GitHub Advisory

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2026-71417 has been found in lemur.
Attackers can target a specific entry point like PUT /api/1/certificates/ over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 7.3/10.
What to do: upgrade lemur to 1.9.3 or later.
If unsure, ask your IT team or search "lemur CVE-2026-71417" on the vendor's site.

CVE-2026-71417 (lemur) — CWE-639 / CVSS v3 7.3
Attack vector: local / no user interaction
Attack surface: PUT /api/1/certificates/ / POST /api/1/certificates/upload / GET /certificates/ / GET /certificates
Patched: 1.9.3 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (CWE-639) exists in lemur. Attackers reach the vulnerable code path via PUT /api/1/certificates/.

📍 Affected scope

Check the vendor advisory for the affected versions of lemur. Attack surface: PUT /api/1/certificates/ / POST /api/1/certificates/upload / GET /certificates/ / GET /certificates.

🔥 Severity

Severity: High (CVSS 7.3/10). Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 1.9.3.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual PUT /api/1/certificates/ requests with malformed payloads or SQL meta-characters. Run grep -r 'lemur' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

  1. 1
    Identify exposure identify 
    grep -r 'lemur' . | grep -v node_modules

    リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で lemur を grep し、稼働しているサービス・バージョンを把握する。

  2. 2
    Hunt for indicators of compromise detect 
    grep 'PUT /api/1/certificates/' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'

    アクセスログで PUT /api/1/certificates/ への異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。

  3. 3
    Apply patch patch 
    Upgrade lemur to 1.9.3

    ステージング環境で 1.9.3 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 2 で見つけた異常検知の続報チェックを含めること。

  4. 4
    Post-deployment verification verify 
    Replay attack against PUT /api/1/certificates/ on staging to confirm patch closes the vector

    パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 2 と同じログクエリでアラート再発が無いか継続監視。

Affected packages

pip lemur
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.9.3"}]}]
PyPI lemur
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.9.3"}]}]

References

We use cookies for analytics and ad measurement. This setting applies to all Game co., Ltd. sites. Details