1. Home
  2. Vulnerabilities
  3. CVE-2026-21728
7.5
HIGH CVSS 3.1
CVE-2026-21728
Tempo query limit results in unbounded memory allocation
Overview
Description

Tempo queries with large limits can cause large memory allocations which can impact the availability of the service, depending on its deployment strategy. Mitigation can be done by setting max_result_limit in the search config, e.g. to 262144 (2^18). Alternatively, automatically restart the service.

Details
INFO

Published Date :

April 24, 2026, 9:16 a.m.

Last Modified :

July 13, 2026, 2:16 p.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Impact
Affected Products

The following products are affected by CVE-2026-21728 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 Grafana tempo
: Total Affected Vendor : 1 | Products : 1
Scoring
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 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Solution
Limit query results to prevent excessive memory usage and ensure service availability.
  • Configure max_result_limit in search settings.
  • Set max_result_limit to a safe value like 262144.
  • Monitor service availability after applying the limit.
References
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-2026-21728.

URL Resource
https://grafana.com/security/security-advisories/cve-2026-21728 Broken Link
https://access.redhat.com/errata/RHSA-2026:21769
https://access.redhat.com/errata/RHSA-2026:22347
https://access.redhat.com/errata/RHSA-2026:22423
https://access.redhat.com/errata/RHSA-2026:23345
https://access.redhat.com/errata/RHSA-2026:24503
https://access.redhat.com/security/cve/CVE-2026-21728
https://bugzilla.redhat.com/show_bug.cgi?id=2461395
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-21728.json
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-21728 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-2026-21728 weaknesses.

CAPEC-147: XML Ping of the Death XML Ping of the Death CAPEC-227: Sustained Client Engagement Sustained Client Engagement CAPEC-492: Regular Expression Exponential Blowup Regular Expression Exponential Blowup CAPEC-125: Flooding Flooding CAPEC-130: Excessive Allocation Excessive Allocation CAPEC-147: XML Ping of the Death XML Ping of the Death CAPEC-197: Exponential Data Expansion Exponential Data Expansion CAPEC-229: Serialized Data Parameter Blowup Serialized Data Parameter Blowup CAPEC-230: Serialized Data with Nested Payloads Serialized Data with Nested Payloads CAPEC-231: Oversized Serialized Data Payloads Oversized Serialized Data Payloads CAPEC-469: HTTP DoS HTTP DoS CAPEC-482: TCP Flood TCP Flood CAPEC-486: UDP Flood UDP Flood CAPEC-487: ICMP Flood ICMP Flood CAPEC-488: HTTP Flood HTTP Flood CAPEC-489: SSL Flood SSL Flood CAPEC-490: Amplification Amplification CAPEC-491: Quadratic Data Expansion Quadratic Data Expansion CAPEC-493: SOAP Array Blowup SOAP Array Blowup CAPEC-494: TCP Fragmentation TCP Fragmentation CAPEC-495: UDP Fragmentation UDP Fragmentation CAPEC-496: ICMP Fragmentation ICMP Fragmentation CAPEC-528: XML Flood XML Flood

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-2026-21728 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-21728 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.

  • CVE Modified by [email protected]

    Jul. 13, 2026

    Action Type Old Value New Value
    Changed Affected [{'vendor': 'Grafana', 'product': 'Tempo', 'versions': [{'status': 'affected', 'version': 'v1.3.0', 'lessThan': 'v2.11.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] [{'vendor': 'Grafana', 'product': 'Tempo', 'versions': [{'status': 'affected', 'version': '1.3.0', 'versionType': 'semver', 'lessThanOrEqual': '2.8.3'}, {'status': 'affected', 'version': '2.9.0', 'versionType': 'semver', 'lessThanOrEqual': '2.9.1'}, {'status': 'affected', 'version': '2.10.0', 'versionType': 'semver', 'lessThanOrEqual': '2.10.1'}], 'defaultStatus': 'unaffected'}, {'vendor': 'Grafana', 'product': 'Enterprise Traces (GET)', 'versions': [{'status': 'affected', 'version': '1.0.0', 'versionType': 'semver', 'lessThanOrEqual': '2.8.7'}], 'defaultStatus': 'unaffected'}]
    Changed Description Tempo queries with large limits can cause large memory allocations which can impact the availability of the service, depending on its deployment strategy. Mitigation can be done by setting max_result_limit in the search config, e.g. to 262144 (2^18). Tempo queries with large limits can cause large memory allocations which can impact the availability of the service, depending on its deployment strategy. Mitigation can be done by setting max_result_limit in the search config, e.g. to 262144 (2^18). Alternatively, automatically restart the service.
  • CVE Modified by 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    Jun. 30, 2026

    Action Type Old Value New Value
    Added Affected [{'cpes': ['cpe:/a:redhat:multicluster_globalhub:1.3::el9'], 'vendor': 'Red Hat', 'product': 'Multicluster Global Hub 1.3.4', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:multicluster_globalhub:1.4::el9'], 'vendor': 'Red Hat', 'product': 'Multicluster Global Hub 1.4.5', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:multicluster_globalhub:1.5::el9'], 'vendor': 'Red Hat', 'product': 'Multicluster Global Hub 1.5.4', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:multicluster_globalhub:1.6::el9'], 'vendor': 'Red Hat', 'product': 'Multicluster Global Hub 1.6.2', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:multicluster_globalhub:1.7::el9'], 'vendor': 'Red Hat', 'product': 'Multicluster Global Hub 1.7.1', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:ceph_storage:5'], 'vendor': 'Red Hat', 'product': 'Red Hat Ceph Storage 5', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:ceph_storage:6'], 'vendor': 'Red Hat', 'product': 'Red Hat Ceph Storage 6', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:ceph_storage:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Ceph Storage 9', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:openshift_distributed_tracing:3'], 'vendor': 'Red Hat', 'product': 'Red Hat OpenShift distributed tracing 3', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:logging:6'], 'vendor': 'Red Hat', 'product': 'Logging Subsystem for Red Hat OpenShift', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:multicluster_globalhub'], 'vendor': 'Red Hat', 'product': 'Multicluster Global Hub', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:acm:2'], 'vendor': 'Red Hat', 'product': 'Red Hat Advanced Cluster Management for Kubernetes 2', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:10'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9', 'defaultStatus': 'unaffected'}]
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-770
    Added Reference https://access.redhat.com/errata/RHSA-2026:21769
    Added Reference https://access.redhat.com/errata/RHSA-2026:22347
    Added Reference https://access.redhat.com/errata/RHSA-2026:22423
    Added Reference https://access.redhat.com/errata/RHSA-2026:23345
    Added Reference https://access.redhat.com/errata/RHSA-2026:24503
    Added Reference https://access.redhat.com/security/cve/CVE-2026-21728
    Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2461395
    Added Reference https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-21728.json
  • Initial Analysis by [email protected]

    Jun. 29, 2026

    Action Type Old Value New Value
    Added CPE Configuration OR *cpe:2.3:a:grafana:tempo:*:*:*:*:*:*:*:* versions from (including) 1.3.0 up to (excluding) 2.8.4 *cpe:2.3:a:grafana:tempo:*:*:*:*:*:*:*:* versions from (including) 2.10.0 up to (excluding) 2.10.2 *cpe:2.3:a:grafana:tempo:*:*:*:*:*:*:*:* versions from (including) 2.9.0 up to (excluding) 2.9.2
    Added Reference Type Grafana Labs: https://grafana.com/security/security-advisories/cve-2026-21728 Types: Broken Link
  • CVE Modified by [email protected]

    Jun. 17, 2026

    Action Type Old Value New Value
    Changed Affected [{'vendor': 'Grafana', 'product': 'Tempo', 'versions': [{'status': 'affected', 'version': 'v1.3.0', 'lessThan': 'v2.11.0', 'versionType': 'semver'}], 'platforms': ['OnPrem'], 'defaultStatus': 'unaffected'}] [{'vendor': 'Grafana', 'product': 'Tempo', 'versions': [{'status': 'affected', 'version': 'v1.3.0', 'lessThan': 'v2.11.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 17, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-21728', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-04-24T11:29:58.649315Z'}
  • CVE Modified by [email protected]

    Jun. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Grafana', 'product': 'Tempo', 'versions': [{'status': 'affected', 'version': 'v1.3.0', 'lessThan': 'v2.11.0', 'versionType': 'semver'}], 'platforms': ['OnPrem'], 'defaultStatus': 'unaffected'}]
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Apr. 24, 2026

    Action Type Old Value New Value
    Added CWE CWE-400
  • New CVE Received by [email protected]

    Apr. 24, 2026

    Action Type Old Value New Value
    Added Description Tempo queries with large limits can cause large memory allocations which can impact the availability of the service, depending on its deployment strategy. Mitigation can be done by setting max_result_limit in the search config, e.g. to 262144 (2^18).
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added Reference https://grafana.com/security/security-advisories/cve-2026-21728
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.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.5
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact