Cisco SD-WAN Zero-Day Exploitation Tied to Volt Typhoon’s ‘Silent Train’ Network
Source SecurityWeek
Exploited in the wild · KEV due 27 Feb 2026 : block it and hunt for it in your logs now.
Data as of 29 Oct 2026, 12:32 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else. Other KEV due dates
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 25 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
Exploited in the wildExploited: evidence found.
Listed in CISA KEV the same day as disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by Cisco Systems, Inc.
, 140 days before disclosure
CVE published
on cve.org
, t = 0
In Threat Radar
record ingested
, 6 hours after disclosure
Added to CISA KEV (opens in a new tab)
exploitation confirmed
, the same day as disclosure
KEV remediation due
US federal deadline
, 2 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| CiscoCisco Catalyst SD-WAN Manager | Affected
| Fixed in– |
Description
A critical zero-day vulnerability (CVE-2026-20127) in Cisco SD-WAN controllers has been exploited by a sophisticated threat actor linked to the Volt Typhoon 'Silent Train' network. The vulnerability allows remote attackers to bypass authentication and gain administrative access to SD-WAN controllers without credentials. Attackers deployed KeyDrift malware to maintain persistent access and steal encryption keys, targeting organizations in sectors such as defense, aerospace, telecommunications, and critical infrastructure. The campaigns have been ongoing since at least late 2025, affecting entities primarily in the United States, with a focus on regions including Hawaii, California, and Texas.