CVE-2026-21725 in Grafana
Summary
by MITRE • 02/25/2026
A time-of-create-to-time-of-use (TOCTOU) vulnerability lets recently deleted-then-recreated data sources be re-deleted without permission to do so.
This requires several very stringent conditions to be met:
- The attacker must have admin access to the specific datasource prior to its first deletion. - Upon deletion, all steps within the attack must happen within the next 30 seconds and on the same pod of Grafana. - The attacker must delete the datasource, then someone must recreate it. - The new datasource must not have the attacker as an admin. - The new datasource must have the same UID as the prior datasource. These are randomised by default. - The datasource can now be re-deleted by the attacker. - Once 30 seconds are up, the attack is spent and cannot be repeated. - No datasource with any other UID can be attacked.
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Analysis
by VulDB Data Team • 03/05/2026
The vulnerability described in CVE-2026-21725 represents a sophisticated time-of-create-to-time-of-use flaw that exploits a temporal window in Grafana's data source management system. This type of vulnerability falls under the CWE-367 category of Time-of-Check to Time-of-Use, where an attacker manipulates the system state between a validation check and actual use of a resource. The flaw specifically targets Grafana's data source deletion mechanism, creating a scenario where an attacker with administrative privileges can exploit a brief temporal gap to perform unauthorized actions on data sources that have been recently deleted and recreated.
The technical implementation of this vulnerability requires precise coordination of multiple system events within an extremely tight temporal window of 30 seconds. The attack exploits the fact that Grafana's data source management system maintains certain metadata or state information during the deletion process that persists briefly after the initial deletion operation. During this window, the system's access control checks may not yet have been fully updated to reflect the deletion status, allowing an attacker who previously had administrative access to the data source to perform deletion operations on a recreated data source. This temporal inconsistency creates a window where the system's integrity checks fail to properly validate the attacker's permissions against the new instance of the data source.
The operational impact of this vulnerability extends beyond simple unauthorized deletion, as it demonstrates a fundamental flaw in Grafana's access control and state management mechanisms. Attackers who successfully exploit this vulnerability can effectively bypass access controls for data source management, potentially leading to data exposure, service disruption, or the ability to manipulate critical system components. The restriction that the attack must occur on the same pod and within 30 seconds limits the attack surface but does not eliminate the risk, as it still allows for targeted attacks against specific Grafana instances where attackers have administrative access. The requirement for the new data source to maintain the same UID means that attackers must carefully orchestrate their attack to ensure UID reuse, making the attack more complex but not impossible to execute.
The mitigation strategies for this vulnerability must address both the temporal window and the underlying access control issues. Organizations should implement immediate access revocation procedures for administrative accounts, particularly when data sources are deleted or modified. The most effective long-term solution involves modifying Grafana's internal state management to ensure that access control validation occurs consistently throughout the entire lifecycle of data source operations, eliminating the temporal gap that enables this attack. Additionally, implementing more robust UID management and ensuring that deleted data source identifiers are not immediately reusable can prevent attackers from exploiting the specific conditions required for this vulnerability. This vulnerability also highlights the importance of implementing proper audit logging and monitoring for data source operations, as such attacks would likely generate suspicious activity patterns that could be detected through behavioral analysis. The attack pattern aligns with techniques described in the MITRE ATT&CK framework under the Privilege Escalation and Defense Evasion tactics, where attackers manipulate system state to bypass security controls. Organizations should also consider implementing additional validation checks that ensure proper state transitions and prevent unauthorized operations on resources that are in transition states, as this represents a classic example of how temporal inconsistencies in security controls can be exploited by determined attackers.