Vulnerability in lemur (CVE-2026-71322)
Summary
Vulnerability in lemur (CVE-2026-71322). Risk of unauthorized operations or information disclosure. Exploitable via CertificateExport. Mitigation: upgrade to 1.9.3 or later.
Original description
The description as published by the source.
Summary
The CertificateExport handler in lemur/certificates/views.py nests its entire ownership / CertificatePermission check inside an if plugin.requires_key: branch. When the selected export plugin advertises requires_key = False, the authorization check is skipped entirely and any authenticated user can invoke plugin.export(cert.body, cert.chain, cert.private_key, options) against a certificate they do not own. The handler additionally writes a "key_view" audit-log event for every call, regardless of whether the plugin actually accessed the private key, polluting the audit trail with false positives.
Root Cause
lemur/certificates/views.py:1573:
if plugin.requires_key:
if not cert.private_key:
return (..., 400)
else:
if g.current_user != cert.user:
owner_role = role_service.get_by_name(cert.owner)
permission = CertificatePermission(owner_role, [x.name for x in cert.roles])
if not permission.can():
return (..., 403)
log_service.create(g.current_user, "key_view", certificate=cert) # always logged
extension, passphrase, data = plugin.export(
cert.body, cert.chain, cert.private_key, options
)
The authorization gate is structurally inside the if plugin.requires_key: block. With requires_key = False, control falls straight through to plugin.export(...) with no ownership check. The cert.private_key is passed to the plugin regardless of the flag…
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-2026-71322 has been found in lemur.
Attackers can target a specific entry point like CertificateExport over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 4.3/10.
What to do: upgrade lemur to 1.9.3 or later.
If unsure, ask your IT team or search "lemur CVE-2026-71322" on the vendor's site.
CVE-2026-71322 (lemur) — CWE-862 / CVSS v3 4.3
Attack vector: remote (network-reachable) / no user interaction
Attack surface: CertificateExport / CertificatePermission / cert.private_key / ExportPlugin
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.
A vulnerability (CWE-862) exists in lemur. Attackers reach the vulnerable code path via CertificateExport.
Check the vendor advisory for the affected versions of lemur. Attack surface: CertificateExport / CertificatePermission / cert.private_key / ExportPlugin.
Severity: Medium (CVSS 4.3/10). Risk of unauthorized operations or information disclosure.
Update to 1.9.3.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. 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
-
1Identify 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。 -
2Apply 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を含めること。
-
3Post-deployment verification verify
Confirm patched version is live in production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。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- package github.com
- package pypi.org
- web github.com
- web github.com
- web github.com