High severity · published Jul 9, 2026
CVE-2026-31984
DoS through oversized audit log entries in Guardian/CMC before 26.2.0
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
A denial-of-service vulnerability caused by unbounded resource allocation was discovered in the audit logging functionality, due to a missing size limit on input recorded into audit entries. An unauthenticated attacker can submit requests containing excessively large input that is recorded into audit entries, possibly exhausting the available disk space and rendering the system inoperable.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 43% 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-2026-31984
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-31984
Mitigation
https://security.nozominetworks.com/NN-2026:11-01
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-827968.html
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