Dos

Security incidents tagged Dos. Newest first.

1 Dos incident in the last 12 months

Critical 4 · High 3 · Med 2 · Low 1 · Update ½Severity-weighted: critical 4 · high 3 · medium 2 · low 1 · update ½LessMore

Patched
Cisco ASA and FTD zero-day CVE-2026-76418 exploited to crash SSL VPN firewalls
Cisco patched CVE-2026-76418 (CVSS 8.6), a denial-of-service bug in the Remote Access SSL VPN service of Secure Firewall ASA and Secure Firewall Threat Defense (FTD) software. Logic errors when secondary authentication is configured on a tunnel group let an unauthenticated, remote attacker send a crafted request while connecting to the SSL VPN and make the device reload; a successful VPN login is not needed. Cisco PSIRT became aware of active exploitation in October 2026 and strongly recommends upgrading. Devices are affected when webvpn is enabled on an interface and a tunnel group (including DefaultWEBVPNGroup) uses secondary-authentication-server-group. There is no workaround, but disabling secondary authentication mitigates it. Shadowserver tracks more than 51,000 internet-exposed ASA SSL VPN devices.
Cisco Secure Firewall ASA and Secure Firewall Threat Defense (FTD)Since Oct 28, 2026updated Oct 29, 2026, 11:23 UTC

Cisco ASA and FTD zero-day CVE-2026-76418 exploited to crash SSL VPN firewalls
The Hacker News
@TheHackersNews
🚨 Cisco patches actively exploited ASA and FTD firewall flaw. CVE-2026-76418 (CVSS 8.6) can let unauthenticated attackers remotely crash affected firewalls, causing denial of service. No successful VPN login required. Details + affected versions ↓ t.co/c0xxNRltVP
Oct 29, 2026view on x