Microsoft recently revealed a critical security flaw in its Teams application for Android, which could permit authenticated attackers to access sensitive data via network exploitation. Identified as CVE-2026-42835, this vulnerability was disclosed on June 9, 2026, and has been deemed Important in its severity level.
Details of the Security Flaw
The vulnerability arises from improper neutralization of special elements in outputs used by downstream components, categorized under CWE-74 (Injection). Microsoft’s advisory indicates that an attacker could remotely access information without needing user interaction.
This flaw has a CVSS 3.1 base score of 8.1, with a temporal score of 7.1, highlighting the significant risk involved. Classified with a Network attack vector (AV:N), it confirms that the vulnerability can be exploited over the internet.
Impact and Exploitability
The vulnerability’s low attack complexity (AC:L) suggests that attackers do not require extensive knowledge of the target system, making exploitation relatively straightforward. A successful exploitation could allow attackers to access small portions of heap memory, potentially exposing sensitive data like authentication tokens and session information.
While the data exposed may appear minimal, the contents of heap memory can include critical runtime information, posing a serious threat in enterprise environments. The CVSS metrics reveal a high impact on Confidentiality and Availability, with no integrity impact, and a low privilege requirement suggests that even users with minimal access could exploit the vulnerability.
Mitigation and Recommendations
Microsoft has classified the likelihood of exploitation as Less Likely, with no public disclosure or active exploitation reported so far. The maturity of exploit code is marked as Unproven, and a fix is already available.
The company has issued a security update for Microsoft Teams on Android, accessible via the Google Play Store. Users and administrators are urged to promptly update the application to safeguard against potential breaches.
Given the widespread use of Teams for managing sensitive business communications and file sharing, organizations should prioritize this update to maintain the security of their internal communications.
This vulnerability was responsibly disclosed by Ofek Levin from Enclave, through Microsoft’s coordinated vulnerability disclosure program.
