CVE-2026-76378

Executive Summary

CVE-2026-76378 is an information disclosure vulnerability affecting versions of the Cisco Secure Malware Analytics app for Splunk SOAR prior to 2.4.5. The flaw arises because the application fails to mark the sample_password parameter of the "detonate file" action as a password-type field, causing this sensitive value to be displayed in cleartext in the Splunk SOAR user interface. This exposure is exploitable only by users who already hold a role with permission to run actions—requiring pre-existing authenticated access with action-execution privileges. With a CVSS score of 4.3 (Medium), the vulnerability is confidentiality-impacting only, and no patch evidence has been identified across tracked sources as of this writing. Enterprises running affected versions of the Cisco Secure Malware Analytics app in their Splunk SOAR environment should treat the stored cleartext password as compromised for any sample analysis workflow and apply immediate mitigation measures.

Technical Analysis

The vulnerability mechanism centers on improper handling of sensitive parameter metadata within the Splunk SOAR action framework. When a Splunk SOAR app defines an action, it can designate certain parameters with a "password" or "secret" property that tells the platform to mask the value both during input and in the action's output/execution results. In this case, the Cisco Secure Malware Analytics app's "detonate file" action defines a sample_password parameter without this masking designation, despite the parameter being intended to carry a sensitive authentication credential used when detonating (executing) a malware sample in the sandbox environment.

The root cause maps to CWE-312 (Cleartext Storage of Sensitive Information). Specifically, this is the UI-presentation variant of that weakness: the sensitive value is not encrypted at rest or improperly handled in transit but rather is exposed directly in the application's rendered interface. The Splunk SOAR platform, when rendering action execution results and invocation parameters, will display parameter values as literal text unless the app's JSON action definition explicitly marks the parameter with the appropriate password field type. Because the app omits this designation, the sample_password value appears verbatim in the Splunk SOAR UI for any user with visibility to the action's execution history.

The attack surface is restricted to authenticated Splunk SOAR users who hold roles granting the "run an action" permission. This includes analysts, automation engineers, or any operator who can invoke and view the execution details of the "detonate file" action. The vulnerability does not require network-level access to the underlying Cisco Secure Malware Analytics API—the exposure occurs entirely within the Splunk SOAR platform's user interface layer. The scope of leaked information is limited: the sample_password credential associated with the configured sample detonation workflow. This credential may grant access to the Cisco Secure Malware Analytics (Threat Grid) API, potentially allowing lateral movement into the sandbox service's management plane if the same credential is reused elsewhere.

Exact code-level details—such as the specific JSON schema field names within the app's action definitions or the Splunk SOAR API endpoints involved—are not provided in the NVD description beyond the acknowledged sample_password parameter name and the "detonate file" action name. No public proof-of-concept or exploit code has been identified, and the vulnerability class suggests that exploitation is trivially achieved through normal platform usage: a privileged user simply invokes the action and observes the cleartext parameter in the execution details pane. No privilege escalation or bypass of authentication controls is required—the flaw is purely a visibility/redaction failure.

Exploitation Scenarios

Attack Chain (inferred from vulnerability class; no public PoC available):

1. Reconnaissance / Target Identification: An attacker who is an insider (malicious or complacent) must first have an authenticated account on the Splunk SOAR platform with a role granting the "run an action" permission. This is typically an analyst or automation role. The attacker identifies the Cisco Secure Malware Analytics app as a configured app and specifically targets the "detonate file" action, which is commonly used to submit suspicious files for dynamic analysis. The attacker may also be a contractor or third-party operator with legitimate but temporary access.

2. Triggering the Flaw: The attacker navigates to the Splunk SOAR UI, invokes the "detonate file" action, and populates the sample_password field with a known or guessed value—or simply reviews the execution history of prior runs performed by other users. Because the parameter is not marked as a password-type field, the Splunk SOAR platform does not mask its value in the action's input parameters view or in the execution results. The sensitive value is rendered as plain text.

3. Payload / Execution Method: There is no traditional "payload" in this vulnerability. The execution method is the normal usage of the Splunk SOAR "detonate file" action's invocation and result-viewing interface. The attacker does not need to craft malformed input or exploit a memory-corruption class issue. The disclosure occurs either (a) passively, by browsing the execution history of the action and reading the cleartext sample_password value, or (b) actively, by running the action with the existing credential stored in the app's configuration, which the UI then reveals after execution.

4. Post-Exploitation Impact: With the leaked sample_password, the attacker gains knowledge of the credential used to authenticate to the Cisco Secure Malware Analytics (Threat Grid) sandbox service. If this credential is reused across other systems (a common and dangerous practice), the attacker can pivot to the Threat Grid API, submit/retrieve samples, disable sandboxing protections, or access other linked accounts where the same password is used. The confidentiality impact is rated Low (C:L) in the CVSS vector because the exposed secret is a single credential, not a broad data set; however, the actual business impact depends entirely on credential reuse and the sensitivity of the Threat Grid environment.

Impact Assessment

CVSS Breakdown: The vulnerability scores 4.3 (Medium) under CVSS:3.1 with vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N. The network attack vector (AV:N) reflects that the Splunk SOAR platform is typically accessed over the network. Low attack complexity (AC:L) indicates no special conditions are needed to trigger the flaw. The low privileges required (PR:L) acknowledges that an authenticated user with action-run permission is necessary. No user interaction is required (UI:N). The scope is unchanged (S:U). Confidentiality impact is Low (C:L) because a single credential is exposed, while integrity and availability are unaffected (I:N/A:N).

Affected Systems: Any Splunk SOAR deployment (on-premises or cloud) running the Cisco Secure Malware Analytics app in a version below 2.4.5. The vulnerability specifically affects environments where the app's "detonate file" action is configured with a non-empty sample_password value—i.e., where the sandbox integration actually uses password-based authentication. Environments that run the app in a default configuration without a password set are not exposed.

Business Impact: The primary business risk is credential exposure leading to unauthorized access to the malware-analysis sandbox. For security operations centers (SOCs) leveraging this integration, a leaked sandbox credential could allow an insider or a credential-harvesting attacker to tamper with the analysis environment—e.g., by poisoning sample databases or bypassing detonation checks—thereby undermining the integrity of the SOC's malware-detection pipeline. Additionally, if credentials are reused across other internal systems (Active Directory, cloud consoles, etc.), the lateral movement risk increases substantially. The cleartext storage also violates compliance requirements for organizations subject to data-protection mandates, potentially exposing them to regulatory penalties.

Blast Radius: The blast radius is confined to Splunk SOAR users with action-execution roles and the connected Cisco Secure Malware Analytics tenant. It does not extend to network-level exploitation or unauthenticated access. However, the long-term storage of cleartext credentials in UI execution logs means the exposure window may extend indefinitely, as historical execution records will retain the visible password until explicitly purged.

Detection Guidance

Sigma Rule

title: Splunk SOAR - Cisco Malware Analytics Cleartext Password Exposure
id: 8e1f2a3c-4d5e-6f7a-8b9c-0d1e2f3a4b5c
status: experimental
description: Detects access to Cisco Secure Malware Analytics app execution results in Splunk SOAR where the detonate file action reveals a cleartext sample_password parameter.
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2026-76378
author: vartersit.com Threat Intel Team
date: 2026/01/15
logsource:
    product: splunk
    service: soar
detection:
    selection_soar_audit:
        EventType: 'ActionExecuted'
        ActionName: 'detonate file'
    selection_param_exposure:
        ParameterName: 'sample_password'
        ParameterMasked: 'false'
    condition: selection_soar_audit and selection_param_exposure
level: high
falsepositives:
    - Legitimate debugging sessions by authorized Splunk SOAR administrators viewing action parameters for troubleshooting
fields:
    - TargetUser
    - SourceAddress
    - ActionName
    - sample_password
tags:
    - attack.t1555
    - attack.t1005
    - cve.2026.76378

YARA Rule

rule CVE_2026_76378_SplunkSOAR_CleartextPassword
{
    meta:
        author = "valtersit.com Threat Intel Team"
        description = "Detects cleartext sample_password parameter exposure in Cisco Secure Malware Analytics app for Splunk SOAR logs and execution records"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-76378"
        cve = "CVE-2026-76378"
        date = "2026-01-15"
        severity = "medium"
    strings:
        $a = "detonate file" ascii wide nocase
        $b = "sample_password" ascii wide nocase
        $c = "masked\":" ascii wide
        $d = "cisa" ascii wide
    condition:
        all of ($a, $b, $c) and #d < 2
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-76378 - Splunk SOAR cleartext sample_password in detonate file action"; flow:established,to_server; content:"detonate%20file"; nocase; content:"sample_password"; nocase; pcre:"/sample_password[\"'=: ]{1,}[^&\"']{4,}/is"; classtype:attempted-recon; sid:2026076378; rev:1; reference:cve,2026-76378;)

Elastic Detection

sequence by host.name with maxspan=5m
  [authentication where event.action == "authenticated" and
     winlog.event_id == 4624 and
     winlog.logon.type == 3 and
     user.name != null]
  [file where event.category == "file" and
     event.action == "write" and
     process.executable : "splunksoar*" and
     file.name : "*action*" and
     process.command_line : "*sample_password*"]
  [process where event.category == "process" and
     process.executable : "splunksoar*" and
     process.command_line : "*detonate*file*"]

Splunk SPL Query

index=splunk_soar OR index=soar_audit sourcetype=soar:action 
| where ActionName="detonate file" AND ParameterName="sample_password" AND ParameterMasked=false
| table _time, TargetUser, SourceAddress, ActionName, ParameterName, ParameterValue
| eval exposure_flag=if(ParameterMasked==false, "CLEARTEXT_PASSWORD_EXPOSED", "OK")
| where exposure_flag="CLEARTEXT_PASSWORD_EXPOSED"
| stats count by TargetUser, SourceAddress, _time
| sort - count

Wazuh OSSEC Rule

<group name="splunk_soar,">
  <rule id="100087" level="12">
    <if_sid>100001</if_sid>
    <match>detonate file</match>
    <regex>sample_password.*masked.*false</regex>
    <description>CVE-2026-76378: Cisco Secure Malware Analytics app for Splunk SOAR exposed sample_password in cleartext via detonate file action.</description>
    <group>cve-2026-76378,</group>
    <mitre>
      <id>T1005</id>
    </mitre>
  </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 0/4 — UNPATCHED. No patch evidence has been identified from any tracked source. The vendor, Cisco, has not published a fixed version advisory at the time of this writing. The affected-versions list is provided by NVD as version range "< 2.4.5" (i.e., all versions prior to 2.4.5 are affected), but 2.4.5 itself has not been confirmed as a patched release.

Immediate Mitigations (until a vendor patch is available):

1. Restrict access: Audit and limit the set of Splunk SOAR roles that have the permission to run the "detonate file" action. Only grant this to least-privilege roles that absolutely require it for daily SOC operations. Reject any request for blanket access.
2. Rotate the credential: Treat the sample_password value currently configured in the app as compromised. Immediately rotate the credential for the Cisco Secure Malware Analytics (Threat Grid) account and update the app configuration with the new value. Consider rotating any credential that resembles or reuses the same password.
3. Disable the action: If the "detonate file" action is non-critical to current operations, disable it entirely in the app's configuration until a patch is applied.
4. Monitor execution history: Instruct SOC administrators to review the execution history of the "detonate file" action for any prior runs where the password may have been viewed or captured in logs/screenshots. Purge sensitive execution records if retention policies permit.

Patch/Upgrade Steps:

1. Monitor Cisco's official advisory portal and the Splunk app store for an updated version of the Cisco Secure Malware Analytics app. Apply the updated app version (expected to be 2.4.5 or later) as soon as it is released.
2. Prior to upgrade, inventory all configured instances of the app across Splunk SOAR deployments and document any customizations that may interfere with the upgrade process.
3. After upgrading, verify that the sample_password parameter is now masked in the UI by running a test detonation and confirming the value is redacted.

Long-Term Hardening:

1. Never reuse credentials: Ensure the Cisco Secure Malware Analytics API credential is unique and dedicated to this integration only; never reuse it for other services.
2. Enable centralized secret management: Integrate Splunk SOAR with a secrets manager (e.g., HashiCorp Vault) where supported, rather than storing credentials directly in the app configuration.
3. Adopt least-privilege role design: Regularly review Splunk SOAR roles and permissions, removing any roles that grant action execution rights but do not explicitly need them for their primary duties.
4. Implement audit logging: Enable comprehensive audit logging for the Splunk SOAR platform and configure alerts for any action execution involving sensitive parameters.
5. Track vendor advisories: Subscribe to Cisco's security advisory feed and Splunk's app release notes to receive immediate notification of any patch release for this CVE.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2026-76378 — Official NVD record containing the description, CVSS vector (4.3/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N), CWE-312 classification, and version-range details.
2. Splunk SOAR Documentation — Run an Action: https://help.splunk.com/en/splunk-soar/soar-on-premises/use-splunk-soar-on-premises/8.6.0/use-the-command-line-interface-to-perform-tasks-in-splunk-soar-on-premises/run-an-action-in-splunk-soar-on-premises — Official Splunk reference describing how Splunk SOAR actions and their parameters are executed and rendered; directly referenced in the NVD description as the source of guidance on action parameter behavior.
3. CWE-312 — Cleartext Storage of Sensitive Information: https://cwe.mitre.org/data/definitions/312.html — MITRE Common Weakness Enumeration entry describing the weakness class mapped to this CVE.
4. Cisco Secure Malware Analytics (Threat Grid) Product Page: https://www.cisco.com/c/en/us/products/security/threat-grid/index.html — Vendor product page for the sandbox service whose credential is exposed; useful for understanding the downstream impact of a leaked sample_password.

Known Threat Actor Campaigns / Exploit-in-the-Wild: None identified at the time of writing. CISA KEV status is NO, indicating the vulnerability has not been cataloged as actively exploited in known exploited-vulnerabilities lists. No public exploit code, Nuclei template, or Metasploit module has been published. The attack mechanism relies purely on authenticated UI interaction, and its discovery likely results from internal security auditing or responsible-disclosure research.