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CISA Adds Six Exploited Flaws to KEV, Including NetScaler, Linux, and SQL Server Bugs

CISA added six actively exploited flaws to KEV, led by Citrix NetScaler CVE-2026-8452, with federal patch deadlines set.

CISA added six flaws to the KEV catalog on August 27, 2026, citing evidence of active exploitation, led by CVE-2026-8452, an improper buffer restriction in Citrix NetScaler ADC and Gateway that can cause denial-of-service. Defused Cyber and Previdian reported active exploitation of CVE-2026-8452, with 36 attempts over 12 days from 12 attacker IPs deploying web shells x.php and z.php. The other additions cover SQL Server RCE (CVE-2019-1068), Linux kernel out-of-bounds write (CVE-2022-0995), Red Hat ABRT and libuser privilege escalations (CVE-2015-5287, CVE-2015-3246), and AjaxPro deserialization RCE (CVE-2021-23758). FCEB agencies must patch CVE-2019-1068 and CVE-2026-8452 by August 29, 2026, and the rest by September 9, 2026.

The Hacker News · 21d agoExploit / PoC in the wildCVE-2019-1068CVE-2026-8452CVE-2022-0995+3 CVEs1

U.S. CISA adds Red Hat, Linux Kernel, Ajax.NET Professional, Microsoft SQL Server, and Citrix NetScaler flaws to its Known Exploited Vulnerabilities catalog

CISA added six flaws, including actively exploited CVE-2026-8452 in Citrix NetScaler, to its Known Exploited Vulnerabilities catalog with federal patch deadlines.

CISA added six vulnerabilities to its KEV catalog: CVE-2015-3246 and CVE-2015-5287 (Red Hat libuser race condition and ABRT privilege escalation), CVE-2019-1068 (Microsoft SQL Server RCE), CVE-2021-23758 (Ajax.NET Professional deserialization), CVE-2022-0995 (Linux Kernel out-of-bounds write) and CVE-2026-8452 (Citrix NetScaler ADC/Gateway memory buffer flaw). CVE-2026-8452 has been observed under active exploitation in the wild and can cause denial-of-service. Under BOD 22-01, federal civilian agencies must patch CVE-2019-1068 and CVE-2026-8452 by August 29, 2026, and the rest by September 9, 2026.

Security Affairs · 20d agoExploit / PoC in the wildCVE-2015-3246CVE-2015-5287CVE-2019-1068+3 CVEs

Cisco ASA and FTD DoS Vulnerability Exploited in the Wild (CVE-2026-20349)

Cisco patched actively exploited high-severity flaw CVE-2026-20349 in ASA and FTD SSL VPN services, allowing unauthenticated remote denial-of-service attacks.

Cisco released a security advisory addressing CVE-2026-20349, a high-severity vulnerability in the Remote Access SSL VPN service of Cisco Secure Firewall ASA and FTD Software. Successful exploitation by an unauthenticated remote attacker can cause affected devices to crash or reload, causing denial of service. The vulnerability is being exploited in the wild, and patches are available; organizations with internet-exposed ASA/FTD VPN endpoints should prioritize updating.

Qualys ThreatPROTECT · Aug 13, 2026Exploit / PoC in the wildCVE-2026-20349

Cisco security advisory (AV26-197) – Update 3

CISA added Cisco CVE-2026-20079 to its KEV catalog; the Canadian Cyber Centre urges updates across Secure Firewall ASA, FTD, FMC, and SCC products.

The Canadian Centre for Cyber Security updated advisory AV26-197 covering March 2026 Cisco advisories for Security Cloud Control, Secure Firewall Management Center, ASA, and FTD. Cisco confirmed CVE-2026-20131 was actively exploited on March 18, 2026, and CISA added it to KEV on March 19. In Update 3, dated September 9, 2026, CISA added CVE-2026-20079 to the KEV catalog. The underlying flaws include FMC authentication bypass and remote code execution, ASA TCP-flood denial of service, and ASA/FTD IPsec denial of service.