Medium severity · published Jan 13, 2021
CVE-2021-1236
Multiple Cisco products are affected by a vulnerability in the Snort application detection engine that could allow an unauthenticated, remote attacker to bypass the configured…
5.3
CVSS
2.2%
EPSS
No
On KEV
Description
Multiple Cisco products are affected by a vulnerability in the Snort application detection engine that could allow an unauthenticated, remote attacker to bypass the configured policies on an affected system. The vulnerability is due to a flaw in the detection algorithm. An attacker could exploit this vulnerability by sending crafted packets that would flow through an affected system. A successful exploit could allow the attacker to bypass the configured policies and deliver a malicious payload to the protected network.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.2% · higher than 82% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IX
IOS XE · Cisco
before 17.4.1 · source: NVD
SF
Secure Firewall Management Center · Cisco
2.9.14.0; 2.9.14.14; 2.9.15; 2.9.16; 2.9.17 · source: NVD
SF
Secure Firewall Threat Defense · Cisco
before 6.5.0.5 · source: NVD
SN
Snort · Snort
before 2.9.14 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-1236
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-1236
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-app-bypass-cSBYCATq
www.debian.org
https://www.debian.org/security/2023/dsa-5354
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