Skip to content
Fencer Vulns
medium 5.5

CVE-2021-31232 json

Improper input validation in CNCF Cortex

published 2021-04-30 5 y ago modified 2026-06-17 4 mo ago also GHSA-m45g-f45x-vv22 , GO-2022-0915 , EUVD-2021-1352

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 31%
public exploits
0
none known

Summary

The Alertmanager in CNCF Cortex before 1.8.1 has a local file disclosure vulnerability when -experimental.alertmanager.enable-api is used. The HTTP basic auth password_file can be used as an attack vector to send any file content via a webhook. The alertmanager templates can be used as an attack vector to send any file content because the alertmanager can load any text file specified in the templates list.

Patch / fix

  • go github.com/cortexproject/cortex 1.8.1
  • linuxfoundation cortex 1.8.1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-31232 updated cvss 5.5

cortex: Alertmanager can expose local files content via specially crafted config

  • Red Hat Openshift Container Storage 4 ocs4/mcg-rhel8-operator, ocs4/ocs-rhel8-operator
    affected: no fix planned “Out of support scope”
  • Red Hat Logging Subsystem for Red Hat OpenShift openshift-logging/logging-loki-rhel8 Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/thanos-rhel7, rhacm2/acm-grafana-rhel8, rhacm2/acm-prometheus-rhel8, rhacm2/rbac-query-proxy-rhel8, rhacm2/thanos-receive-controller-rhel8 Red Hat Enterprise Linux 8 grafana, grafana-loki, grafana-mssql, grafana-mysql, grafana-selinux, grafana-graphite, +8 more Red Hat Enterprise Linux 9 grafana, grafana-selinux Red Hat OpenShift Container Platform 4 openshift4/ose-grafana, openshift4/ose-thanos-rhel8, openshift4/ose-cluster-storage-operator, openshift4/ose-prometheus-rhel9-operator, openshift4/ose-cluster-monitoring-rhel9-operator Red Hat Openshift Data Foundation 4 odf4/mcg-rhel9-operator, odf4/ocs-rhel9-operator, odf4/odf-rhel8-operator
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.37% chance of exploitation in the next 30 days, higher than 31% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD 2.0 2.1 AV:L/AC:L/Au:N/C:P/I:N/A:N
GitHub 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
go github.com/cortexproject/cortex
<1.8.1
1.8.1

Classification

Weakness
  • CWE-20 Improper Input Validation

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.