CVE-2021-1402: cisco cisco firepower threat defense software
Vulnerability summary
CVE-2021-1402 is a high (CVSS 8.6) vulnerability in cisco cisco firepower threat defense software. EPSS estimates a 1.40% chance of exploitation in the next 30 days, higher than 71.9% of scored vulnerabilities.
Timeline
- 29-04-2021PublishedVulnerability first disclosed.
- 08-11-2024Last modifiedVulnerability information updated.
Description
A vulnerability in the software-based SSL/TLS message handler of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of SSL/TLS messages when the device performs software-based SSL decryption. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message through an affected device. SSL/TLS messages sent to an affected device do not trigger this vulnerability. A successful exploit could allow the attacker to cause a process to crash. This crash would then trigger a reload of the device. No manual intervention is needed to recover the device after the reload.
CVSS metrics
4 scores · 2 sources · 3 versions- NVDNIST8.6HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS trend
Probability
1.40%
Chance of exploitation in the next 30 days
Percentile
72%
Versus all other CVEs
30-day change
+0.01 pp
From 1.39% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
- CWE-20Improper Input ValidationThe product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
Affected systems
Cisco2 products
- cisco firepower threat defense softwaren/a
- secure_firewall_threat_defense≥ 6.3.0, < 6.4.0 | ≥ 6.5.0, < 6.6.0
1 vendor · 2 products
References
1 links- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-ssl-decrypt-dos-DdyLuK6cVendor AdvisoryX Refsource CISCO