CVE-2026-34486: Apache Software Foundation Apache Tomcat
CISA added CVE-2026-34486, an actively exploited Apache Tomcat EncryptInterceptor bypass enabling unauthenticated deserialization RCE, to its KEV catalog.
CVE-2026-34486 allows bypass of Apache Tomcat's EncryptInterceptor, a flaw introduced by the fix for padding-oracle issue CVE-2026-29146 in Tribes cluster encryption. CISA added the flaw to the Known Exploited Vulnerability catalog on August 4, 2026, alongside actively exploited Langflow and N-central flaws, with remediation required under BOD 26-04 guidance. Official patches and workarounds are available, and reporting notes unauthenticated remote code execution through Java deserialization on the Tribes receiver port 4000.
Weekly Cybersecurity Newsletter Bulletin – Microsoft 0-day, FortiOS, PAN-OS Flaw, Revolut Data Breach, and 20+ Stories
Weekly roundup: Microsoft patches 973 flaws including two actively exploited zero-days; FortiOS CAPWAP flaw deploys PivotC2 RAT; PAN-OS root RCE disclosed.
Microsoft's September 2026 Patch Tuesday fixed 973 vulnerabilities, including two zero-days under active exploitation: CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack), both elevation-of-privilege bugs. SOCRadar reported active exploitation of CVE-2025-25249 (CVSS 9.8) in FortiOS CAPWAP, deploying a Node.js RAT called PivotC2 that exfiltrates Exchange mailboxes to Wasabi cloud storage; 178 devices were compromised out of 30,000 scanned IPs, attributed to a Russian-speaking financially motivated group. Palo Alto disclosed CVE-2026-0310, a 9.2-rated buffer overflow enabling root code execution on PA-Series firewalls, and Fortinet disclosed CVE-2026-84393, a ZTNA certificate validation MITM flaw. Cyera also revealed CVE-2026-6471 ('PostGREShell'), a 12-year-old PostgreSQL logical-decoding flaw allowing code execution via REPLICATION-privileged accounts.