CVE-2025-21038 is a medium-severity vulnerability identified in Samsung Mobile's S Assistant application, specifically involving the SamsungExceptionalBroadcastReceiver component. The issue stems from improper verification of intents received by this broadcast receiver prior to version 9.3.2. Broadcast receivers in Android are components that listen for and respond to system-wide or application-specific broadcast messages (intents). Improper verification means that the receiver does not adequately validate the source or content of the intent before processing it. This flaw allows a local attacker—someone with access to the device—to send crafted intents to the vulnerable broadcast receiver, thereby modifying itinerary information managed by the S Assistant app. The vulnerability is classified under CWE-925, which relates to improper verification of intent, a common security weakness in Android applications that can lead to unauthorized actions or data manipulation. The CVSS 3.1 base score is 5.1, indicating a medium severity level. The vector string (AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L) describes that the attack requires local access (AV:L), low attack complexity (AC:L), no privileges (PR:N), no user interaction (UI:N), unchanged scope (S:U), no confidentiality impact (C:N), low integrity impact (I:L), and low availability impact (A:L). There are no known exploits in the wild, and no patches are explicitly linked in the provided data, though the vulnerability affects versions prior to 9.3.2, implying that updating to 9.3.2 or later would remediate the issue. The vulnerability does not affect confidentiality but impacts integrity and availability to a limited extent by allowing modification of itinerary data and possibly causing disruption in the S Assistant's functionality. Since the attack vector is local, exploitation requires physical or logical access to the device, reducing the risk of remote exploitation but still posing a threat in scenarios where devices are shared, lost, or compromised by malicious local apps or users.

For European organizations, the impact of CVE-2025-21038 depends largely on the use of Samsung mobile devices with the S Assistant app in their operational environment. The vulnerability allows local attackers to modify itinerary information, which could lead to misinformation, scheduling errors, or disruption of business processes relying on accurate calendar and itinerary data. While the confidentiality of data is not directly compromised, the integrity and availability of itinerary information are at risk. This could affect sectors where precise scheduling is critical, such as logistics, transportation, event management, and corporate environments with mobile workforce coordination. Additionally, if attackers manipulate itinerary data, it could be used as a vector for social engineering or to cause operational delays. The requirement for local access limits the threat to insiders or attackers who have gained physical or logical access to devices, such as through malware or unauthorized use. However, in environments with lax device security policies or shared devices, the risk increases. The absence of known exploits in the wild suggests the threat is currently theoretical but should be addressed proactively to prevent future exploitation. Organizations with mobile device management (MDM) systems that include Samsung devices should prioritize patching and monitoring for suspicious local activity related to the S Assistant app.

1. Update all Samsung devices running the S Assistant app to version 9.3.2 or later, where the vulnerability is fixed. 2. Enforce strict device access controls, including strong authentication and screen locks, to prevent unauthorized local access. 3. Utilize Mobile Device Management (MDM) solutions to monitor and control app installations and permissions, restricting the ability of untrusted apps to send intents to system components. 4. Educate users about the risks of installing untrusted applications and the importance of not sharing devices. 5. Implement application whitelisting or sandboxing to limit the ability of local apps to interact with sensitive broadcast receivers. 6. Regularly audit device logs for unusual intent broadcasts or modifications to itinerary data. 7. If updating is delayed, consider disabling or restricting the S Assistant app where feasible, especially on devices used in sensitive roles. 8. Collaborate with Samsung support channels to obtain official patches and security advisories promptly.