CVE-2020-3548
A vulnerability in the Transport Layer Security (TLS) protocol implementation of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause high CPU usage on an affected device,…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.84%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A vulnerability in the Transport Layer Security (TLS) protocol implementation of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause high CPU usage on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to inefficient processing of incoming TLS traffic. An attacker could exploit this vulnerability by sending a series of crafted TLS packets to an affected device. A successful exploit could allow the attacker to trigger a prolonged state of high CPU utilization. The affected device would still be operative, but response time and overall performance may be degraded.There are no workarounds that address this vulnerability.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.84% probability · 56th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-407
- Affected
- cisco/email security appliance
- Source
- psirt@cisco.com
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.