CyberSecBulletin
CVE-2026-28377NVD status: Analyzed

Tempo: Inadequate Encryption Strength

Published Updated By the CyberSecBulletin desk

CVE-2026-28377 is a high-severity inadequate encryption strength vulnerability in Tempo from Grafana, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Tempo versions: 2.10.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.16% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Tempo you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on grafana.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
GrafanaTempo2.10.3Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by CNA (grafana.com).

Official description

A vulnerability in Grafana Tempo exposes the S3 SSE-C encryption key in plaintext through the /status/config endpoint, potentially allowing unauthorized users to obtain the key used to encrypt trace data stored in S3. Thanks to william_goodfellow for reporting this vulnerability.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Inadequate Encryption Strength

The product stores or transmits sensitive data using an encryption scheme that is theoretically sound, but is not strong enough for the level of protection required.

How developers prevent this class of flaw

  • Use an encryption scheme that is currently considered to be strong by experts in the field.

More Inadequate Encryption Strength vulnerabilities (CWE-326)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Tempo

All Tempo vulnerabilities

Recent Inadequate Encryption Strength vulnerabilities

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