Cisco security advisory (AV26-807)
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
Serial number: AV26-807 Date: August 12, 2026 As of August 11, 2026, Cisco is affected by a vulnerability in the following products: Cisco Secure Firewall Adaptive Security Appliance (ASA) Software multiple versions Cisco Secure Firewall Threat Defense (FTD) Software multiple versions The Cyber Centre encourages users and administrators to review the provided web links and apply any necessary updates as they become available. On August 11, 2026, Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2026-20349 to their Known Exploited Vulnerabilities (KEV) Database. Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Denial of Service Vulnerability Cisco Security Advisories CISA KEV: CVE-2026-20349
CSIRTS triage
- What
- A denial of service vulnerability exists in the Remote Access SSL VPN component.
- Who is affected
- Deployments of Cisco ASA running affected versions.
- Urgency
- High; the vulnerability is actively exploited in the wild as confirmed by CISA KEV database listing.
- Action
- Apply security updates from Cisco as they become available; review the Cisco Security Advisories for patch details.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://cyber.gc.ca/en/alerts-advisories/cisco-security-advisory-av26-807
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2026-20349Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 56% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-20349 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- highexploitedAL26-018 - Vulnerability affecting Cisco ASA and Secure Firewall Threat Defense Software Remote Access SSL VPN…cccs
- unknownexploitedNCSC-2026-0295 [1.00] [M/H] Vulnerability patched in Cisco Secure Firewall ASA and FTD softwarencsc-nl
- highexploited[NEW] [high] Cisco ASA (Adaptive Security Appliance) and Secure Firewall Threat Defense: Vulnerability enables…cert-bund
- unknownexploitedCisco Products Multiple Vulnerabilitieshkcert
- unknownexploitedVulnerability in Cisco products (August 12, 2026)cert-fr-avis
- highexploitedCVE-2026-20349: A vulnerability in the Remote Access SSL VPN service for Cisco Secure Firewall Adaptive Securi…nvd
- highexploitedCisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SS…cisco-psirt
- highexploitedCISA Adds Three Known Exploited Vulnerabilities to Catalogcisa
- criticalexploitedCVE-2026-20349: Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FT…cisa-kev
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