CVE-2025-40743
Published: 12 August 2025
Summary
CVE-2025-40743 is a high-severity Authentication Bypass Using an Alternate Path or Channel (CWE-288) vulnerability. Its CVSS base score is 8.7 (High).
Operationally, ranked at the 24.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-24245
Vulnerability details
A vulnerability has been identified in SINUMERIK 828D PPU.4 (All versions < V4.95 SP5), SINUMERIK 828D PPU.5 (All versions < V5.25 SP1), SINUMERIK 840D sl (All versions < V4.95 SP5), SINUMERIK MC (All versions < V1.25 SP1), SINUMERIK MC V1.15…
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(All versions < V1.15 SP5), SINUMERIK ONE (All versions < V6.25 SP1), SINUMERIK ONE V6.15 (All versions < V6.15 SP5). The affected application improperly validates authentication for its VNC access service, allowing access with insufficient password verification. This could allow an attacker to gain unauthorized remote access and potentially compromise system confidentiality, integrity, or availability.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Authorizing remote access reduces the ability to bypass authentication via unauthorized alternate remote channels.
Users can identify logons via alternate paths or channels by reviewing the previous logon time.
Adaptive requirements can apply across access paths, reducing the ability to bypass authentication via alternate channels or paths.
Centralized IdPs close alternate authentication paths that enable bypass.
Enforces authentication for non-organizational users, making it harder to bypass via alternate paths or channels.
Requires authentication to occur exclusively over the isolated trusted path, directly preventing bypass via alternate or untrusted channels.