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TempoApplication · Grafana

CVE-2026-27878

MEDIUM · 6.5 CVSS v3.1 Published 2026-06-19
Fix available
A fix is available. Upgrade to 2.8.4 / 2.9.2 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A TraceQL query in Grafana Tempo with a large exemplars hint value can cause the Tempo instance to allocate an excessive amount of memory, resulting in an out-of-memory crash. This could allow an authenticated user to trigger a denial of service against the Tempo service.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Grafana Tempo versions prior to the fix contain a memory exhaustion vulnerability in the TraceQL query engine. When processing a TraceQL query with an excessively large 'exemplars hint' value, the query processor fails to enforce proper bounds, causing uncontrolled memory allocation that can lead to an out-of-memory crash and denial of service.

MitigationImplement input validation and enforce maximum limits on the exemplars hint value in TraceQL queries. Consider applying query complexity limits or query timeouts as additional defense-in-depth measures.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
TempoApplication
Affected:>= 2.6.0, < 2.8.4>= 2.9.0, < 2.9.2>= 2.10.0, < 2.10.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Grafana Tempo installation and version
    Locate the Tempo binary, container, or service and retrieve its version information (e.g., tempo --version, docker image tag, helm release, or /ready endpoint response)
    Affected if the installed version falls within >= 2.6.0 and < 2.8.4, OR >= 2.9.0 and < 2.9.2, OR >= 2.10.0 and < 2.10.2
  2. Confirm TraceQL query engine is in use
    Verify that TraceQL query endpoints are accessible or enabled in the Tempo configuration (typically at /api/traces endpoints or via query frontend)
    Affected if TraceQL query processing is available and accepting queries
  3. Determine if exemplar-based queries are possible
    Check if users or automated systems can submit TraceQL queries containing an 'exemplars' hint or tag (e.g., { span.exemplars(...) } syntax)
    Affected if the exemplars hint feature in TraceQL is accessible without validation limits

You are affected if Grafana Tempo is running a version within the affected ranges AND TraceQL with the exemplars hint feature is accessible to process untrusted queries.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2.8.4 / 2.9.2 / 2.10.2 or later
Fixed in 2.8.42.9.22.10.2
Interim mitigation

Implement input validation and enforce maximum limits on the exemplars hint value in TraceQL queries. Consider applying query complexity limits or query timeouts as additional defense-in-depth measures.

Recommended fix High confidence

Upgrade to Tempo 2.8.4, 2.9.2, or 2.10.2 (or later respective versions)

  1. 1. Identify the current Grafana Tempo version running in your environment
  2. 2. Based on your current version, determine the appropriate upgrade path: if running 2.6.x-2.8.3, upgrade to 2.8.4 or later; if running 2.9.0-2.9.1, upgrade to 2.9.2 or later; if running 2.10.0-2.10.1, upgrade to 2.10.2 or later
  3. 3. Review the Grafana Tempo release notes for the target version for any migration notes or configuration changes
  4. 4. Backup your Tempo configuration and data directory before upgrading
  5. 5. Perform the upgrade following standard Grafana Tempo upgrade procedures
  6. 6. Verify the Tempo service starts successfully and monitor memory usage
Caveat Review release notes for any breaking changes between your current version and target version; minor version upgrades typically have minimal breaking changes

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Tempo Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,130
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,408.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-27878 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data