CVE-2022-35932 is a medium-severity vulnerability affecting Nextcloud Talk, a video and audio conferencing application integrated within the Nextcloud platform. The vulnerability exists in versions prior to 12.2.7, 13.0.7, and 14.0.3. Specifically, password-protected conversations in these versions are susceptible to brute force attacks if an attacker obtains the conversation link or token. This flaw is categorized under CWE-359, which involves the exposure of private personal information to unauthorized actors. The vulnerability arises because the password protection mechanism for conversations can be brute forced, allowing an attacker with access to the conversation token to guess the password and gain unauthorized access to the conversation content. This can lead to exposure of sensitive audio, video, and chat data. There are no known workarounds other than avoiding the use of password-protected conversations until the application is updated. The recommended mitigation is to upgrade Nextcloud Talk to versions 12.2.7, 13.0.7, or 14.0.3 or later, where the issue has been addressed. No exploits are currently known to be in the wild, but the vulnerability presents a clear risk if an attacker can obtain conversation tokens and attempt brute force attacks against the password protection.

For European organizations, this vulnerability could lead to unauthorized disclosure of sensitive communications conducted via Nextcloud Talk, including confidential business discussions, personal data, and potentially regulated information under GDPR. Exposure of such data could result in reputational damage, regulatory penalties, and loss of trust. Organizations relying on Nextcloud Talk for secure internal or external communications may face risks of eavesdropping or data leakage if attackers obtain conversation tokens. The impact is heightened for sectors with strict data privacy requirements such as finance, healthcare, and government entities. Additionally, the breach of confidentiality could facilitate further attacks, including social engineering or targeted espionage. Since the vulnerability requires possession of the conversation token, the risk is partially mitigated by the secrecy of these tokens; however, if tokens are leaked or intercepted (e.g., via phishing, insider threat, or network compromise), the vulnerability becomes exploitable. The integrity and availability of the Nextcloud Talk service are less directly impacted, but confidentiality breaches alone are significant given the nature of the data involved.

1. Immediate upgrade of Nextcloud Talk to versions 12.2.7, 13.0.7, or 14.0.3 or later to patch the vulnerability. 2. Implement strict access controls and monitoring to prevent unauthorized access to conversation tokens, including auditing token generation, distribution, and usage. 3. Educate users on the importance of safeguarding conversation links and tokens, discouraging sharing over insecure channels such as email or instant messaging. 4. Where possible, disable password-protected conversations temporarily until the patch is applied to eliminate the attack vector. 5. Employ network security measures such as TLS encryption and endpoint security to reduce the risk of token interception. 6. Monitor logs for repeated failed password attempts on conversations to detect brute force attempts early. 7. Consider integrating multi-factor authentication or additional verification layers for accessing sensitive conversations if supported by Nextcloud Talk or via custom configurations. 8. Regularly review and update security policies related to the use of conferencing tools and sensitive data handling within the organization.