Medium severity · published Jun 19, 2026
CVE-2026-27878
Tempo TraceQL query with exemplar hint could result in unbounded memory usage
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GR
Grafana · Grafana
2.6.1 before 2.8.8 · source: vendor
TE
Tempo · Grafana
2.6.0 before 2.8.4; 2.9.0 before 2.9.2; 2.10.0 before 2.10.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-27878
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-27878
Broken Link
https://grafana.com/security/security-advisories/cve-2026-27878
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