Medium severity · published Jul 9, 2026
CVE-2026-31983
Missing authentication in SSH keys synchronization endpoint in Guardian/CMC before 26.2.0
5.3
CVSS
0.4%
EPSS
No
On KEV
Description
A Missing Authentication vulnerability was discovered in the SSH keys synchronization endpoint. An unauthenticated attacker can send a request to the SSH keys synchronization endpoint and obtain the list of users that have uploaded their public SSH keys, their groups, and the uploaded public SSH keys.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CM
CMC · Nozomi Networks
before 26.2.0 · source: vendor, NVD
GU
Guardian · Nozomi Networks
before 26.2.0 · source: vendor, NVD
RA
RUGGEDCOM APE1808 · Siemens
0 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-31983
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-31983
Mitigation
https://security.nozominetworks.com/NN-2026:10-01
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-827968.html
More from CMC
8.9
CVE-2025-40899
Stored Cross-Site Scripting (XSS) in Assets and Nodes in Guardian/CMC before 26.0.0
8.1
CVE-2026-33390
Incorrect privilege assignment for Arc sensors in Guardian/CMC before 26.2.0
8.1
CVE-2025-40897
Incorrect authorization for Threat Intelligence in Guardian/CMC before 26.0.0
7.5
CVE-2026-33389
Disabled and non-configurable certificate/host key validation in Smart Polling in Guardian/CMC before 26.3.0 and Arc before v2.7.0
7.5
CVE-2026-31984
DoS through oversized audit log entries in Guardian/CMC before 26.2.0