CVE-2026-86128
Watchguard Fireware: null pointer dereference can lead to denial of service
- Risk score
- 56/100
- CVSS
- 7.5 v3.1
- Exploit chance (30 days)
- 0.4%
- Published
- 30 Sep 2026
Open in the live forecast Today's forecast
What to know
- What it is
- A NULL pointer dereference vulnerability in Fireware OS's NetFlow packet-processing feature allows a remote, unauthenticated attacker to cause a denial of service by sending a specially crafted IPv6 packet.
- Affected
- Watchguard Fireware
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Story map
At a glance
Watchguard Fireware: Amber, patch this week. A code injection vulnerability in WatchGuard Fireware OS's BOVPN Over TLS client configuration handling allows an attacker who controls the remote VPN server to execute arbitrary commands as root on the connecting Firebox.
The flaws
- CVE-2026-86128: Null pointer dereference can lead to denial of service (CVSS 7.5 · EPSS 0%)
- CVE-2026-86131: Code injection (CVSS 9.8 · EPSS 0%)
- CVE-2026-86134: Null pointer dereference can lead to denial of service (CVSS 7.5 · EPSS 0%)
- CVE-2026-86104: Denial of service (CVSS 7.5 · EPSS 0%)
The fix
Fix: Apply the vendor's security update; see the linked advisory.
Who is exposed: Watchguard Fireware
Where it stands
- No known exploitation
Connects to
- Same weakness: Null pointer dereference (CWE-476). 91 other warnings in 30 days
- Same product: Earlier Watchguard Fireware warnings. 10 in the last 90 days
Why it is Yellow
- CVSS 7.5 high
- Remotely exploitable without logging in
References
Original description
A NULL pointer dereference vulnerability in Fireware OS's NetFlow packet-processing feature allows a remote, unauthenticated attacker to cause a denial of service by sending a specially crafted IPv6 packet.
Last activity 30 Sep 2026. Patch Forecast updates every hour.