CVE-2022-23605 is a vulnerability identified in the Wire Webapp, a web client for the Wire messaging protocol. The issue pertains to improper removal of sensitive information before storage or transfer, classified under CWE-212. Specifically, in versions of Wire Webapp prior to 2022-01-27-production.0, expired ephemeral messages were not reliably deleted from the local chat history. Although these messages are intended to be ephemeral and thus transient, the flaw allowed them to remain accessible locally through the search functionality. When a user attempts to view one of these expired messages in the chat interface, the deletion process is then triggered, but until that point, the sensitive ephemeral content remains retrievable. This vulnerability affects only locally stored messages on the client side and does not impact messages stored on the server or transmitted over the network. The issue is particularly relevant for on-premise deployments of Wire Webapp, which require updating to version 2022-01-27-production.0 or later to mitigate the risk. No known workarounds exist, and no exploits have been reported in the wild to date. The vulnerability arises from insufficient sanitization and removal of sensitive ephemeral data, potentially exposing confidential information that users expect to be deleted automatically. The flaw compromises the confidentiality of ephemeral messages, which are often used for sensitive communication due to their transient nature.

For European organizations, especially those relying on Wire Webapp for secure communications, this vulnerability could lead to unintended exposure of sensitive ephemeral messages stored locally on user devices. This exposure risks confidentiality breaches, particularly in sectors handling sensitive data such as finance, healthcare, legal, and government agencies. Since ephemeral messages are designed to disappear, users may have a false sense of security, increasing the risk of sensitive information leakage if devices are shared, lost, or compromised. The impact is limited to local device compromise scenarios; however, in environments with shared or less secure endpoints, the risk is amplified. The vulnerability does not affect message integrity or availability but undermines trust in the ephemeral messaging feature. European organizations with on-premise Wire Webapp deployments are at higher risk, as cloud-hosted instances may be updated by the vendor more promptly. The lack of known exploits reduces immediate risk, but the potential for data leakage remains significant, especially in high-security environments.

The primary mitigation is to update all on-premise Wire Webapp instances to version 2022-01-27-production.0 or later, which includes the fix for this vulnerability. Organizations should implement strict update policies to ensure timely patching of communication tools. Additionally, endpoint security controls should be enhanced to limit unauthorized access to local storage where ephemeral messages reside. Employing disk encryption and secure user authentication can reduce the risk of local data exposure. Organizations should also educate users about the limitations of ephemeral messaging and the importance of device security. For environments where immediate patching is not feasible, restricting local search functionality or disabling ephemeral messaging temporarily may reduce exposure, although these are not official workarounds. Regular audits of local data storage and logs can help detect residual sensitive information. Finally, integrating endpoint detection and response (EDR) solutions can help monitor for suspicious access to local message stores.