CVE-2022-24799 is a cross-site scripting (XSS) vulnerability identified in the wire-webapp, the web interface for the Wire messaging service. The root cause is insufficient escaping of user input during markdown code highlighting, which allows an attacker to inject arbitrary HTML and JavaScript code. When a victim user views a maliciously crafted message, the injected script executes in the context of their browser session. This enables the attacker to fully compromise the victim's Wire user account, potentially accessing sensitive communications and impersonating the user. Additionally, Wire desktop clients connected to a vulnerable wire-webapp instance are also susceptible to this attack vector. The vulnerability affects all versions of wire-webapp prior to 2022-03-30-production.0. The vendor has released a fix in version 2022-03-30-production.0, which is already deployed on all Wire-managed services. However, on-premise deployments must manually update to docker tag 2022-03-30-production.0-v0.29.2-0-d144552 or wire-server 2022-03-30 (chart/4.8.0) to remediate the issue. No known workarounds exist, making patching the only effective mitigation. The vulnerability was responsibly disclosed by researcher Posix and has no known active exploits in the wild as of the publication date. This vulnerability is classified under CWE-79, indicating improper neutralization of input during web page generation, a common vector for XSS attacks. The attack requires that the victim views the malicious message, but no authentication bypass is needed beyond the victim being logged into their Wire account. The impact is significant due to the ability to hijack user sessions and potentially pivot to further attacks within the compromised account.

For European organizations using Wire for internal or external communications, this vulnerability poses a moderate to high risk. Successful exploitation could lead to account takeover, exposing sensitive corporate communications, intellectual property, and personal data. Given Wire's focus on secure messaging, organizations relying on it for confidential discussions may face reputational damage and regulatory consequences if data confidentiality is breached. The compromise of user accounts could also enable attackers to impersonate employees, facilitating social engineering or spear-phishing campaigns within the organization. Wire desktop clients connected to vulnerable webapp instances increase the attack surface, potentially affecting endpoint security. The lack of workarounds means that unpatched on-premise deployments remain exposed until updated, increasing risk for organizations managing their own Wire infrastructure. While no active exploits are known, the ease of injecting malicious code via message content and the broad impact on confidentiality and integrity make this a significant threat to European enterprises, especially those in regulated sectors such as finance, healthcare, and government.

1. Immediate patching of all on-premise wire-webapp instances to version 2022-03-30-production.0 or later is critical. Use the specified docker tag (2022-03-30-production.0-v0.29.2-0-d144552) or wire-server chart (4.8.0) to ensure full remediation. 2. Verify that all Wire-managed services are running the patched version; coordinate with service providers to confirm updates. 3. Conduct an audit of user accounts and recent message activity to detect any suspicious behavior indicative of compromise. 4. Implement strict content filtering and monitoring on messaging platforms to detect and block suspicious markdown or code snippets that could exploit similar vulnerabilities. 5. Educate users on the risks of clicking unknown or unexpected links and viewing messages from untrusted sources, emphasizing caution even within trusted communication channels. 6. For organizations with on-premise deployments, establish a rapid patch management process to minimize exposure windows for critical vulnerabilities. 7. Monitor Wire security advisories and vulnerability disclosures for any updates or emerging exploit information. 8. Consider deploying Content Security Policy (CSP) headers and other browser security mechanisms to limit the impact of potential XSS attacks where feasible.