CVE-2020-3548 Cisco Email Security Appliance Denial Of Service Vulnerability
Unauthenticated remote attackers can cause high CPU usage and degraded performance on Cisco Email Security Appliances by sending crafted TLS packets.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2020-3548?
CVE-2020-3548 is a medium-severity denial of service vulnerability in Cisco Email Security Appliance, published on 18 Nov 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-407
Which versions are affected by CVE-2020-3548?
It affects 1 product.
Products include Cisco Email Security Appliance.
How do I fix CVE-2020-3548?
No fix has been published for CVE-2020-3548 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2020-3548 being exploited?
There is no known exploitation of CVE-2020-3548 in the wild and no public exploit code.
Other vulnerabilities in Cisco Email Security Appliance
- CVE-2022-20798 Cisco Email Security Appliance and Cisco Secure Email and Web Manager External Authentication Bypass Vulnerability
- CVE-2015-6291 Denial of service in n/a
- CVE-2022-20664 Cisco Email Security Appliance and Cisco Secure Email and Web Manager Information Disclosure Vulnerability
- CVE-2022-20960 Denial of service in Cisco Secure Email
- CVE-2018-0419 Security feature bypass in Email Security Appliance (ESA)
Sources
Also known as GHSA-r24r-r242-xm9f.