CVE-2026-20295CWE-789

CVE-2026-20295

High · published September 17, 2026

CVSS v3.1
8.6
EPSS
1%
Percentile
45.2
In the wild
Unconfirmed
What it is

A vulnerability in the sftunnel inter-device communication protocol of Cisco Secure FMC Software and Cisco Secure FTD Software could allow an unauthenticated, remote attacker to exhaust the available memory of an affected device.

This vulnerability is due to improper management of memory resources during sftunnel TLS connection setup. An attacker could exploit this vulnerability by sending crafted sftunnel TLS frames to an affected device during the connection setup. A successful exploit could allow the attacker to exhaust the available memory on the affected device, which could result in a DoS condition.

The record
Technical detail
CVSS v3.1
8.6 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00549 · 45.2th percentile
Weakness
CWE-789 · Memory Allocation with Excessive Size Value
Published
2026-09-17T01:17Z
References (1)
EPSS history
Timeline
  • 18 SEP 03:58Z
    EPSS moved — → 1%
    epss
  • 16 SEP 20:09Z
    Cisco Secure Firewall Management Center and Secure Firewall Threat Defense Software sftunnel Memory Exhaustion Denial of Service Vulnerability
    cvelistv5