Security readout for executives and security teams
Plain-English summary
Splunk MCP Server app versions below 1.2.1 allow a Splunk administrator to turn malicious stored credential data into operating-system commands. Successful abuse could expose data, alter systems, or interrupt service. The attacker must already hold the powerful admin role, but compromise of that account could escalate into control of the underlying host.
Executive priority
Treat as an urgent privileged-access risk. Prioritize internet-reachable, sensitive, or high-value Splunk systems and environments with weak administrator controls. Upgrade promptly, then review privileged access and telemetry. Immediate emergency response is not established solely by the supplied evidence because active exploitation has not been confirmed.
Technical view
The credential management component deserializes stored data without validating its expected type, creating CWE-502 unsafe deserialization. Network-accessible exploitation requires a Splunk user with the admin role and no user interaction. Successful exploitation can execute arbitrary operating-system commands with high confidentiality, integrity, and availability impact and a changed security scope.
Likely exposure
Exposure is limited to deployments running Splunk MCP Server app versions below 1.2.1. Practical risk depends on whether administrators can reach the app and whether admin credentials are compromised or misused. The supplied sources do not identify affected host operating systems, deployment configurations, or additional prerequisites.
Exploitation context
The CVSS 3.1 score is 9.1, reflecting low complexity but high required privileges. The supplied record is not in CISA KEV, and no cited source establishes active exploitation or public exploit availability. Absence from KEV does not prove the vulnerability is not being exploited.
Researcher notes
The trust-boundary change is important: an application-level Splunk administrator may gain command execution on the host. Investigation should focus on the credential management component, stored serialized data, admin actions, and correlated host activity. The sources do not disclose implementation details, affected privileges on the operating system, indicators of compromise, or exploit reliability.
Mitigation direction
- Upgrade the Splunk MCP Server app to version 1.2.1 or a vendor-supported later release.
- Review Splunk's advisory for any deployment-specific remediation or compensating controls.
- Restrict admin-role assignment to essential personnel and remove unnecessary privileged accounts.
- Protect administrator access with strong authentication and tightly controlled network reachability.
Validation and detection
- Inventory every Splunk deployment and record the installed MCP Server app version.
- Confirm no instance runs a version below 1.2.1.
- Review admin-role membership for unexpected, stale, or excessive assignments.
- Examine relevant audit and host telemetry for unexplained credential changes or operating-system command execution.
- Verify the upgraded app operates normally and security monitoring remains active.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-502: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-76404 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H2.36ciscoVulnerability scoring details
Base CVSS 3.1 score
9.1CriticalVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://advisory.splunk.com/advisories/SVD-2026-0808CVE reference, cisco
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Deserialization of Untrusted Data
Deserialization of Untrusted Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.