Critical severity · published Sep 8, 2026
CVE-2026-58240
Missing Authentication check in SAP NetWeaver (Message Server)
9.8
CVSS
0.5%
EPSS
No
On KEV
Description
SAP NetWeaver Message Server does not sufficiently validate the authenticity of internal application server components during registration. An unauthenticated attacker with network access to the affected service could exploit this weakness to register an unauthorized component and potentially perform unauthorized actions within the application environment, resulting in a high impact on the confidentiality, integrity, and availability of the affected system.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 45% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SN
SAP NetWeaver (Message Server) · SAP_SE
KERNEL 9.16; 9.18; 9.19; 9.20 · source: vendor