8.8
HIGH CVSS 3.1
CVE-2026-48508
Lemur: Authorization bypass in StrictRolePermission / AuthorityCreatorPermission
Description

Lemur manages TLS certificate creation. Prior to 1.9.1, StrictRolePermission and AuthorityCreatorPermission in lemur/auth/permissions.py call flask_principal.Permission.__init__() with zero Need objects when ADMIN_ONLY_AUTHORITY_CREATION and LEMUR_STRICT_ROLE_ENFORCEMENT are unset because both flags default to False. Flask-Principal Permission.allows() returns True when self.needs is empty, so the .can() authorization gate permits every authenticated identity, including the read-only role. A read-only user can access POST /api/1/authorities, POST /api/1/certificates/upload, POST /api/1/pending_certificates//upload, POST /api/1/notifications, PUT or DELETE /api/1/notifications/, and POST /api/1/domains to create root Certificate Authorities, upload arbitrary certificates, create or edit notifications that reach an SSRF sink, and create domain entries. Explicitly setting either flag to False continues to opt into the permissive behavior. This issue is fixed in version 1.9.1.

INFO

Published Date :

Aug. 18, 2026, 6:17 p.m.

Last Modified :

Aug. 18, 2026, 6:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-48508 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Netflix lemur
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update Lemur to version 1.9.1 or later to address an authorization bypass vulnerability.
  • Update Lemur to version 1.9.1 or later.
  • Ensure ADMIN_ONLY_AUTHORITY_CREATION is properly configured.
  • Ensure LEMUR_STRICT_ROLE_ENFORCEMENT is properly configured.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-48508.

URL Resource
https://github.com/Netflix/lemur/commit/e6a41e2c1b2028840d19039b06895524a19ad36f
https://github.com/Netflix/lemur/releases/tag/v1.9.1
https://github.com/Netflix/lemur/security/advisories/GHSA-qcqw-jwxc-2hqg
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-48508 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-48508 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-48508 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-48508 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 18, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Netflix', 'product': 'lemur', 'versions': [{'status': 'affected', 'version': '< 1.9.1'}]}]
    Added Description Lemur manages TLS certificate creation. Prior to 1.9.1, StrictRolePermission and AuthorityCreatorPermission in lemur/auth/permissions.py call flask_principal.Permission.__init__() with zero Need objects when ADMIN_ONLY_AUTHORITY_CREATION and LEMUR_STRICT_ROLE_ENFORCEMENT are unset because both flags default to False. Flask-Principal Permission.allows() returns True when self.needs is empty, so the .can() authorization gate permits every authenticated identity, including the read-only role. A read-only user can access POST /api/1/authorities, POST /api/1/certificates/upload, POST /api/1/pending_certificates//upload, POST /api/1/notifications, PUT or DELETE /api/1/notifications/, and POST /api/1/domains to create root Certificate Authorities, upload arbitrary certificates, create or edit notifications that reach an SSRF sink, and create domain entries. Explicitly setting either flag to False continues to opt into the permissive behavior. This issue is fixed in version 1.9.1.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-863
    Added Reference https://github.com/Netflix/lemur/commit/e6a41e2c1b2028840d19039b06895524a19ad36f
    Added Reference https://github.com/Netflix/lemur/releases/tag/v1.9.1
    Added Reference https://github.com/Netflix/lemur/security/advisories/GHSA-qcqw-jwxc-2hqg
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.