CVE-2020-27124

CVE-2020-27124 is a high-severity vulnerability in Cisco Adaptive Security Appliance Software with a CVSS 3.x base score of 8.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-457.

Key facts

Description

A vulnerability in the SSL/TLS handler of Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause the affected device to reload unexpectedly, leading to a denial of service (DoS) condition. The vulnerability is due to improper error handling on established SSL/TLS connections. An attacker could exploit this vulnerability by establishing an SSL/TLS connection with the affected device and then sending a malicious SSL/TLS message within that connection. A successful exploit could allow the attacker to cause the device to reload.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

Frequently asked questions

What is CVE-2020-27124?
A vulnerability in the SSL/TLS handler of Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause the affected device to reload unexpectedly, leading to a denial of service (DoS) condition. The vulnerability is due to improper error handling on established SSL/TLS connections. An attacker could exploit this vulnerability by establishing an SSL/TLS connection with the affected device and then sending a malicious SSL/TLS message within that connection. A successful exploit could allow the attacker to cause the device to reload.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
How severe is CVE-2020-27124?
CVE-2020-27124 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-27124 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27124?
CVE-2020-27124 primarily affects Cisco Adaptive Security Appliance Software. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-27124?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2020-27124 have an EU (EUVD) identifier?
Yes. CVE-2020-27124 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-19648.
When was CVE-2020-27124 published?
CVE-2020-27124 was published on 2024-11-18 and last updated on 2026-06-17.

References

Affected products (3)

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