Vulnerability in Grafana Mimir's Alertmanager Exposing Configuration Data
CVE-2026-81938

7.7HIGH

Key Information:

Vendor

Grafana
Status
Enterprise Metrics (gem)
Grafana Mimir
Vendor
CVE Published:
2 November 2026

What is CVE-2026-81938?

Grafana Mimir's Alertmanager has a vulnerability that allows a tenant with upload permissions to leverage specific HTTP client settings, potentially leading to unintended exposure of sensitive files. When a notification is dispatched, if these fields are misconfigured, the Alertmanager may read sensitive information, such as credentials and configuration files, and expose them in outgoing requests. The vulnerability impacts both Grafana Mimir’s Alertmanager and Grafana Enterprise Metrics, necessitating users to upgrade to secure versions to mitigate the risks involved.

Affected Version(s)

Enterprise Metrics (GEM) 2.11.0 <= 2.16.2

Enterprise Metrics (GEM) 2.17.0 < 2.17.20

Grafana Mimir 3.0.4 < 3.1.7

References

https://grafana.com/security/security-advisories/cve-2026...
vendor-advisory

CVSS V3.1

Score:
7.7
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

arang
.