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Threats / Grafana Labs / CVE-2021-39226
CVE-2021-39226 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Grafana Labs vulnerability

Grafana authentication bypass allows authenticated and unauthenticated users to view and delete all snapshot data, causing potential complete data loss.

Verdict

Today item — known-exploited.

An authentication bypass in Grafana permits both authenticated and unauthenticated attackers to access and delete snapshot data without proper authorization, resulting in unauthorized data exposure and destruction.

CISA KEV Yes · 2022-08-253EPSS 0.99951 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
402 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-08-25).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.99951 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Grafana Labs, Grafana. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-287 Improper Authentication — weakness family: Authentication.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I exploit the authentication bypass to access Grafana without valid credentials or escalate my existing limited privileges.
Business
Unauthorized access to monitoring infrastructure creates exposure of sensitive operational metrics and system configurations.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I enumerate and view all snapshot data stored in the Grafana instance, including historical dashboards and reports.
Business
Confidential performance data, capacity planning information, and historical metrics become visible to unauthorized parties.
3

Lateral reach — past segmentation narrative 3

Attacker
I delete all snapshots from the system to disrupt monitoring capabilities and destroy audit trails.
Business
Loss of snapshot data eliminates historical records needed for compliance, forensics, and operational continuity.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • 402 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by GitHub_M (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by GitHub_MCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.