8.1

CVE-2026-71308: netflix lemur

CVSS: 8.1v3.1HighDeferred
AliasesGHSA-cfh6-pv5c-38jvPYSEC-2026-3675
Published 18-08-2026Last modified 18-08-2026

Vulnerability summary

CVE-2026-71308 is a high (CVSS 8.1) vulnerability in netflix lemur. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 23% of scored vulnerabilities.

Overall risk
32/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.32%
0%100%
Low · +0.10 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 18-08-2026
    PublishedVulnerability first disclosed.
  2. 18-08-2026
    Last modifiedVulnerability information updated.

Description

Lemur manages TLS certificate creation. From 0.5.0 until 1.9.3, certificate create, upload, and edit requests accepted replaces[] or replacements identifiers that AssociatedCertificateSchema resolved with fetch_objects without a CertificatePermission check. Assigning those objects to Certificate.replaces invoked an append listener that disabled the victim certificate notifications and marked it as replaced. The victim was then excluded from get_all_pending_reissue, and certificate_rotate could deploy the attacker certificate to endpoints serving the victim. An authenticated non-read-only user could target certificates for which the user had no ownership or role, suppress lifecycle automation, and cause fleet-wide TLS disruption or unauthorized substitution. The fix authorizes every referenced replacement certificate before mutation. This issue is fixed in version 1.9.3.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.32%

Chance of exploitation in the next 30 days

Percentile

23%

Versus all other CVEs

30-day change

+0.10 pp

From 0.22% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.32%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Netflix1 product
PyPI1 product
  • lemur≥ 0.5.0, < 1.9.3

2 vendors · 2 products

References

7 links