Widely deployed Cisco Secure Firewall ASA; DoS could disrupt enterprise networks and VPNs.
CVE-2026-20082
Unauthenticated DoS on Cisco ASA via TCP SYN flood
Is CVE-2026-20082 being exploited?
Not confirmed. CVE-2026-20082 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.41% probability of exploitation in the next 30 days.
How severe is CVE-2026-20082?
CVE-2026-20082 is rated High with a CVSS score of 8.6. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-20082?
Yes. A fix has been recorded for CVE-2026-20082. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-20082 affect?
CVE-2026-20082 affects Cisco Secure Firewall ASA (Adaptive Security Appliance). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-20082?
Apply latest Cisco ASA firmware patch; monitor for SYN flood.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attacker can cause DoS by crafting TCP SYN traffic, blocking management, RAVPN, and TCP services.
Patch when possible
- affected9.20.4.14
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.