CVE-2026-54203

critical

Description

Memory Leak to an Unauthorized Actor vulnerability in Tobit Laboratories AG TeamDavid's Webbox allows reading of sensitive information. When accessing the URL “/.well-known/mta-sts.”, the application responds with memory. By repeatedly requesting this endpoint, an attacker can access sensitive information, including user passwords. Exploitation does not require authentication. This issue affects TeamDavid before Rollout 528. Starting with Rollout 528 (June 30, 2026), the affected functionality is disabled by default and the vulnerabilities are therefore no longer exposed through this functionality.

References

https://labs.infoguard.ch/posts/22-cves-in-david-a-secure-m365-alternative/

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-54435

https://chayns.net/77892-10814/tapp/763210?postId=11454

Details

Source: Mitre, NVD

Published: 2026-08-07

Updated: 2026-10-24

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Severity: High

CVSS v4

Base Score: 9.2

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N

Severity: Critical

EPSS

EPSS: 0.00559