CVE-2026-70667

Lemur manages TLS certificate creation. Prior to 1.9.3, _validate_revocation_url in lemur/certificates/verify.py checked the original CRL or OCSP URL but the later request could reach a different destination. The CRL requests.get call followed HTTP redirects without validating each Location target, so a public attacker-controlled URL could redirect to loopback, RFC1918, link-local, or instance-metadata addresses. Validation and connection also performed separate DNS resolutions, creating a time-of-check time-of-use window for DNS rebinding on both CRL and OCSP paths. An operator uploading a certificate through POST /api/1/certificates/upload could therefore induce blind internal requests despite the earlier mitigation. The fix disables redirects and pins validated addresses while preserving the correct Host value. This issue is fixed in version 1.9.3.

CVSS v3 6.3 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/Netflix/lemur/commit/ed504a830f38a83825b1570302e9f38d6553938a
https://github.com/Netflix/lemur/releases/tag/v1.9.3
https://github.com/Netflix/lemur/security/advisories/GHSA-f3qq-49m6-rw8f
https://github.com/Netflix/lemur/security/advisories/GHSA-54vg-pfh7-jq95

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-18 19:17

Updated : 2026-09-08 21:02

NVD link : CVE-2026-70667

Mitre link : CVE-2026-70667

CVE.ORG link : CVE-2026-70667

JSON object : View

Products Affected

No product.

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

CWE-918

Server-Side Request Forgery (SSRF)

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