Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Netflix lemur — Lemur: SSRF protection in certificate revocation checking bypassable via HTTP redirects and DNS rebinding (incomplete fix for CVE-2026-55162)
AV AC PR UI S C I A CVSS EPSS %ile KEV
N L L N U L L L 6.3 .0014 3.5 —
AFFECTED
Product Versions Fixed
lemur < 1.9.3 – —
TIMELINE
Aug 4 Reserved by GitHub_M
Aug 18 EXPLOIT PUBLISHED — CVE-2026-70667 (Netflix lemur). Public exploit reference added.
Aug 18 Published (CNA: GitHub_M)
Description
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.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
|---|
| August 4, 2026 | Reserved | Reserved by GitHub_M |
| August 18, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-70667 (Netflix lemur). Public exploit reference added. |
| August 18, 2026 | Published | Published (CNA: GitHub_M) |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| Netflix | lemur | — | < 1.9.3 | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-70667 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.