CVE-2020-27124
Cisco Adaptive Security Appliance Software SSL/TLS Denial of Service Vulnerability
- Published
- Updated
- Reserved
- Assigned by
- cisco
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.
Timeline
ID reserved
By cisco
- 4 years later
· 4 years later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ciscoCNA (assigner) | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/RL:X/RC:X/E:X |
| NVDNVD · Analyzed | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.92% · top 39% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Weakness
Affected products
Cisco · Cisco Adaptive Security Appliance (ASA) Software
- affected N/A
What to do
Exploitation: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
References (3)
- cisco-sa-asa-ssl-dos-7uZWwSEy (opens in a new tab)
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sa-rv-routers-xss-K7Z5U6q3 (opens in a new tab)
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-xss-bLZw4Ctq (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-27124)Record last updated .