High severity · published Oct 27, 2021
CVE-2021-40114
Multiple Cisco products are affected by a vulnerability in the way the Snort detection engine processes ICMP traffic that could allow an unauthenticated, remote attacker to cause…
7.5
CVSS
2.5%
EPSS
No
On KEV
Description
Multiple Cisco products are affected by a vulnerability in the way the Snort detection engine processes ICMP traffic that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper memory resource management while the Snort detection engine is processing ICMP packets. An attacker could exploit this vulnerability by sending a series of ICMP packets through an affected device. A successful exploit could allow the attacker to exhaust resources on the affected device, causing the device to reload.
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)2.5% · higher than 84% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SF
Secure Firewall Management Center · Cisco
2.9.14.0; 2.9.15; 2.9.16; 2.9.17 · source: NVD
SF
Secure Firewall Threat Defense · Cisco
before 6.4.0.12; 6.5.0 before 6.6.3; 6.7.0 before 6.7.0.2 · source: NVD
SN
Snort · Snort
2.0.0 before 2.9.18 · source: NVD
UT
Unified Threat Defense · Cisco
16.12 before 16.12.6; 17.3 before 17.3.4a; 17.4 before 17.4.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-40114
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-40114
lists.debian.org
https://lists.debian.org/debian-lts-announce/2023/02/msg00011.html
Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-dos-s2R7W9UU
www.debian.org
https://www.debian.org/security/2023/dsa-5354
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