Medium severity · published Jan 7, 2026
CVE-2026-20026
Multiple Cisco Products Snort 3 DCERPC Vulnerabilities
5.8
CVSS
0.7%
EPSS
No
On KEV
Description
Multiple Cisco products are affected by a vulnerability in the processing of DCE/RPC requests that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to leak sensitive information or to restart, resulting in an interruption of packet inspection.
This vulnerability is due to an error in buffer handling logic when processing DCE/RPC requests, which can result in a buffer use-after-free read. An attacker could exploit this vulnerability by sending a large number of DCE/RPC requests through an established connection that is inspected by Snort 3. A successful exploit could allow the attacker to unexpectedly restart the Snort 3 Detection Engine, which could cause a denial of service (DoS).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CS
Cisco Secure Firewall Threat Defense (FTD) Software · Cisco
7.0.0; 7.0.0.1; 7.0.1; 7.1.0; 7.0.1.1; 7.1.0.1; +34 more · source: vendor
CU
Cisco UTD SNORT IPS Engine Software · Cisco
3.17.1S; 16.12.3; Fuji-16.9.5; 16.12.4; 17.3.1a; 16.6.6; +34 more · source: vendor
Affected product
CS
Cisco Secure Firewall Threat Defense (FTD) Software
Cisco
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-20026
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-20026
sec.cloudapps.cisco.com
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort3-dcerpc-vulns-J9HNF4tH
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