CVE-2021-40116
Last modified
CVE-2021-40116 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Multiple Cisco products are affected by a vulnerability in Snort rules 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 handling of the Block with Reset or Interactive Block with Reset actions if a rule is configured without proper constraints. An attacker could exploit this vulnerability by sending a crafted IP packet to the affected device. EPSS estimates a 1.35% chance of exploitation in the next 30 days.
Description
Multiple Cisco products are affected by a vulnerability in Snort rules 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 handling of the Block with Reset or Interactive Block with Reset actions if a rule is configured without proper constraints. An attacker could exploit this vulnerability by sending a crafted IP packet to the affected device. A successful exploit could allow the attacker to cause through traffic to be dropped. Note: Only products with Snort3 configured and either a rule with Block with Reset or Interactive Block with Reset actions configured are vulnerable. Products configured with Snort2 are not vulnerable.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Firepower Threat Defense | >= 6.4.0, < 6.4.0.13 |
| Cisco | Firepower Threat Defense | >= 6.6.0, < 6.6.5.1 |
| Cisco | Firepower Threat Defense | >= 6.7.0, < 6.7.0.3 |
| Cisco | Firepower Threat Defense | >= 7.0.0, < 7.0.1 |
| Cisco | Secure Firewall Management Center | 3.1.0.1 |
| Cisco | Snort | >= 3.0.0.0, < 3.1.0.100 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
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