CVE-2026-21728: Tempo queries with large limits can cause large memory allocations which can impact the availability of the se

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HIGH 7.5REMOTEUPGRADE

CVE-2026-21728 is a high-severity flaw (CVSS 7.5) affecting tempo. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.6% (top 50%)
CISA exploited list	No
Weakness	CWE-400, CWE-770
Published	2026-04-24
Last modified	2026-10-26

Publisher (CNA): Grafana Labs · Vendor: grafana

Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-24 09:16 UTCPublished CVE record published
2026-10-26 21:10 UTCUpdated Record last modified

grafana tempo UPGRADE

Affected: >= 1.3.0 and < 2.8.4 · >= 2.9.0 and < 2.9.2 · >= 2.10.0 and < 2.10.2

Fixed in: 2.8.4, 2.9.2, 2.10.2

Safe to downgrade to: a release before 1.3.0

1. Check installed version

apt-cache policy tempo || rpm -q tempo || tempo --version

2. UPGRADE to 2.8.4 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade tempo

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade tempo

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 1.3.0 (Debian / Ubuntu)

apt-cache madison tempo sudo apt install tempo=<VERSION_BEFORE_1.3.0> sudo apt-mark hold tempo

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list tempo sudo dnf downgrade tempo-<VERSION_BEFORE_1.3.0> sudo dnf versionlock add tempo

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-21728?

tempo: upgrade to 2.8.4, 2.9.2, 2.10.2. Exact commands for each OS are on this page.

Is CVE-2026-21728 being exploited?

CVE-2026-21728 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-21728 affect?

CVE-2026-21728 affects tempo. Severity is high (CVSS 7.5). 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 262

How urgent is CVE-2026-21728?

Priority 44/100. High severity; Remotely exploitable, no login, no user action

Software pages

Grafana vulnerabilities

References

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