VulnerabilityPublished 3 Dec 2025

CVE-2025-20381: Splunk MCP Server · The software performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.

Affects Splunk MCP ServerSource CVE Database V5

Not known to be exploited · CVSS 5.4 Medium.

Data as of 26 Oct 2026, 09:15 UTC

CVSS 3.1 base score

5.4Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: Low
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 3 Dec 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Splunk Splunk MCP Server	Affected =0.2	Fixed in–

AI-suggested

1. Upgrade Splunk MCP Server to version 0.2.4 or later where the vulnerability is fixed. 2. Restrict access to the "run_splunk_query" MCP tool strictly to trusted and authorized personnel only, minimizing the number of users with such privileges. 3. Implement strict monitoring and logging of MCP tool usage to detect unusual or unauthorized query patterns that could indicate exploitation attempts. 4. Conduct regular audits of user privileges within Splunk environments to ensure least privilege principles are enforced. 5. Employ network segmentation and access controls to limit exposure of the MCP tool to only necessary network segments and users. 6. Develop incident response plans that include scenarios involving misuse of Splunk query capabilities to quickly contain and remediate potential exploitation. 7. Stay informed of vendor advisories and apply patches promptly once available if not already done.

Description

In Splunk MCP Server app versions below 0.2.4, a user with access to the "run_splunk_query" Model Context Protocol (MCP) tool could bypass the SPL command allowlist controls in MCP by embedding SPL commands as sub-searches, leading to unauthorized actions beyond the intended MCP restrictions.

Impact

For European organizations, the vulnerability poses a risk of unauthorized manipulation of Splunk queries, potentially leading to data integrity issues or denial of service conditions within Splunk MCP Server environments. Organizations relying on Splunk for security monitoring, operational intelligence, or compliance reporting could experience inaccurate analytics or disruptions in monitoring capabilities. This could delay incident detection or response, increasing exposure to other threats. The lack of confidentiality impact reduces the risk of data leakage but does not eliminate the risk of operational disruption. The requirement for privileges to access the MCP tool limits exploitation to insiders or attackers who have already gained some level of access, but the bypass of command restrictions elevates the risk of privilege escalation within the Splunk environment. European critical infrastructure sectors, financial institutions, and large enterprises using Splunk MCP Server could be particularly impacted due to their reliance on accurate and reliable data analytics.

References

advisory.splunk.com/advisories/SVD-2025-1210 (opens in a new tab)

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 10 Dec 2025, 18:34 UTC

Technical details

References

Community reviews

Related threats