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AWS Certificate Manager sets 2027 end date for email-validated certificate renewals

AWS Certificate Manager will phase out email validation for public certificates during 2027, requiring migration to DNS validation before September 30, 2027.

AWS Certificate Manager will stop offering email validation in new Regions on January 1, 2027, discontinue it for new certificate requests on March 31, 2027, and stop renewing email-validated certificates on September 30, 2027. This precedes the CA/Browser Forum's March 15, 2028 deadline ending email-based domain validation for publicly trusted certificates. AWS is updating the UpdateCertificateOptions API so customers can switch to DNS validation in place while retaining the certificate ARN, with Route 53 support for creating required CNAME records.

Help Net Security · Aug 14, 2026Advisory

ZTNA Portal Improper Certificate Validation

Fortinet fixed an improper certificate validation flaw (CVSS 7.3) in FortiOS and FortiProxy Agentless ZTNA portal enabling unauthenticated man-in-the-middle attacks on backend traffic.

Fortinet advisory FG-IR-26-174 discloses an improper certificate validation vulnerability (CWE-295) in the FortiOS and FortiProxy Agentless ZTNA portal, rated CVSSv3 7.3. A remote and unauthenticated attacker can perform a man-in-the-middle attack on the communication channel between the ZTNA portal and the backend destination website. The advisory was revised on 2026-09-08.

Fortinet PSIRT · 8d agoAdvisory

ZDI-26-558: (Pwn2Own) Amazon Smart Plug OTA Update Process Improper Certificate Validation Vulnerability

ZDI disclosed a Pwn2Own certificate validation flaw (CVSS 6.8) in Amazon Smart Plug's OTA process, allowing network-adjacent attackers to bypass update verification.

The Zero Day Initiative published ZDI-26-558 for an improper certificate validation flaw in the Amazon Smart Plug OTA update process, demonstrated at Pwn2Own. Network-adjacent attackers need no authentication to bypass certificate validation for over-the-air updates. ZDI rated the issue CVSS 6.8.

ZDI Published Advisories · Aug 12, 2026Advisory

FortiOS and FortiProxy ZTNA Validation Vulnerability Allows Attacker to Perform a Man-in-the-Middle Attack

Fortinet discloses high-severity certificate validation flaw CVE-2026-84393 in FortiOS and FortiProxy Agentless ZTNA portals enabling unauthenticated man-in-the-middle attacks.

Fortinet disclosed CVE-2026-84393 (CVSSv3 7.3, CWE-295) on September 8, 2026 under advisory FG-IR-26-174: improper certificate validation in the Agentless ZTNA portal of FortiOS and FortiProxy. An unauthenticated attacker on the network path could present a forged or mismatched certificate and intercept or tamper with traffic between the portal and backend destinations, with impact classified as information disclosure. Affected versions are FortiOS 7.6.1 through 7.6.6 and FortiProxy 7.6.2 through 7.6.6; the 8.0, 7.4 and 7.2 branches of both products are unaffected. Fortinet urges upgrading to 7.6.7 or later and reports no evidence of exploitation in the wild.

Cyber Security News · 8d agoVulnerabilityCVE-2026-84393

Security Incident – BGP Hijacking

Attackers BGP-hijacked Softaculous' Hetzner IP block for 33 hours, obtained valid TLS certificates, and delivered a malicious Virtualizor update to some servers.

Between August 28 and 30, 2026, AS62390 (NexonHost) announced 162.55.80.0/24 via transit AS6204 (Zet.net) without authorization, diverting traffic while retaining Hetzner's AS24940 on the AS path. The attacker obtained valid Let's Encrypt certificates for virtualizor.com domains because the CA's domain validation was also routed through the hijack, so affected connections showed no TLS warnings. A malicious Virtualizor update package reached a handful of installations; routing was fully restored, and reconstruction from RIPE RIS data showed all 368 collector peers carried the hijacked route at some point with roughly 28% time-weighted diversion.

Lobsters · security · 13d agoData breach

FGFM Authentication Weakening via CLI Configuration

FortiManager FGFM flaw (CVSS 7.3) lets an attacker with a valid certificate impersonate any managed FortiGate under a specific CLI option.

Fortinet advisory FG-IR-26-160 describes an authentication bypass via alternate path (CWE-288) in FortiManager and FortiManager Cloud, scored CVSSv3 7.3. A remote unauthenticated attacker holding a valid certificate can impersonate any FortiGate managed by the affected FortiManager when a specific CLI option is set. The impersonation is performed with crafted FGFM protocol requests. The advisory was revised on 2026-08-12 and does not report active exploitation.

Fortinet PSIRT · Aug 12, 2026Advisory

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.

Cyber Security News · 2d agoExploit / PoC in the wildCVE-2026-85880CVE-2026-81963CVE-2025-25249+3 CVEs3