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CISA: WatchGuard RCE flaw now exploited in ransomware attacks

CISA confirms ransomware gangs are exploiting critical unauthenticated RCE CVE-2025-14733 in WatchGuard Firebox firewalls, with roughly 9,000 devices still unpatched.

CVE-2025-14733 is an out-of-bounds write in WatchGuard Fireware OS allowing unauthenticated remote code execution, exploitable on firewalls configured for IKEv2 VPN and potentially even after the configuration was deleted if a static branch-office VPN peer remains. WatchGuard released patches in December and confirmed in-the-wild exploitation; Shadowserver found over 115,000 exposed Fireboxes at the time, with nearly 9,000 still unpatched after nine months. CISA added the flaw to its Known Exploited Vulnerabilities catalog in December under BOD 22-01 and on Thursday confirmed ransomware gangs are now exploiting it, without providing campaign details. WatchGuard serves more than 250,000 small and mid-sized companies through 17,000+ security resellers and service providers.

Attackers Exploit Zimbra SNMP Flaw for Unauthenticated Remote Code Execution

CERT Polska and CISA report active exploitation of Zimbra RCE CVE-2026-73570, with 267 instances compromised per Shadowserver.

CVE-2026-73570 (CVSS 8.9) enables unauthenticated command injection and remote code execution in Zimbra Collaboration before 10.1.20 when the optional zimbra-snmp package is installed and SNMP notifications are enabled, via crafted SMTP requests. CISA added the flaw to its KEV catalog on August 21, 2026, with a federal patch deadline of August 24. The Shadowserver Foundation counted 267 compromised instances as of August 24, 2026, led by the US (46), Sweden (21), France (20) and Germany (17). Separately, Russia-linked Laundry Bear has weaponized Zimbra stored XSS CVE-2025-66376 against Western government and commercial mail servers since at least July 2025, delivering the ZimReaper payload.

The Hacker News · 21d agoExploit / PoC in the wildCVE-2026-73570CVE-2025-663761

Critical ScreenConnect flaw now actively exploited in attacks

CISA confirms active exploitation of critical ConnectWise ScreenConnect flaw CVE-2026-84869, ordering federal agencies to mitigate within three days.

ConnectWise's ScreenConnect flaw CVE-2026-84869, an improper privilege management and missing authorization bug, lets attackers with basic privileges transfer or execute files through active remote sessions in low-complexity attacks without user interaction. It is patched in ScreenConnect 26.6.5; CISA added it to the KEV catalog and ordered US federal agencies to secure systems within three days. Shadowserver tracks over 1,000 unpatched exposed instances, mostly in North America (758) and Europe (180). This is the fourth actively exploited ScreenConnect flaw since 2024; earlier issues were abused by Kimsuky and ransomware gangs.

BleepingComputerupdated · 3h agofirst · 7h agoExploit / PoC in the wild 5 sourcesCVE-2026-84869CVE-2024-1709CVE-2025-3935+1 CVEs1

Cisco patches Secure Email Gateway zero-day exploited in attacks

Cisco patches actively exploited Secure Email Gateway zero-day CVE-2026-76461 enabling unauthenticated root command execution; CISA adds it to KEV.

Cisco disclosed that a critical zero-day (CVE-2026-76461) in the email parsing logic of AsyncOS for Secure Email Gateway is being actively exploited, allowing unauthenticated remote attackers to execute arbitrary SQL statements that lead to root-level command execution on virtual and physical appliances. CISA added the flaw to its KEV catalog and ordered federal agencies to patch within three days, by September 17. Cisco also patched four other critical SEG/SEWM vulnerabilities (CVE-2026-76440, CVE-2026-76441, CVE-2026-20353, CVE-2026-76443) with no evidence of exploitation, and shared IOCs including suspicious SQL statements in mail_logs.

BleepingComputer · 1d agoExploit / PoC in the wildCVE-2026-76461CVE-2026-76440CVE-2026-76441+3 CVEs

Unpatched Zimbra servers are falling to CVE-2026-73570 attacks

Attackers are exploiting unpatched Zimbra servers via CVE-2026-73570; 274 instances compromised, and CISA added the flaw to its KEV catalog.

The Shadowserver Foundation counted at least 274 compromised internet-facing Zimbra Collaboration Suite instances exploited through CVE-2026-73570, up from 155 on August 20. The unauthenticated code injection flaw affects servers with the optional zimbra-snmp package and SNMP notifications enabled, allowing arbitrary OS command execution via crafted SMTP requests. Synacor patched the issue in ZCS v10.1.20 on July 20, 2026, and at least 8,200 instances remain unpatched. CISA added the flaw to its Known Exploited Vulnerabilities catalog and gave US federal civilian agencies three days to remediate and check for compromise.

Help Net Security · 22d agoExploit / PoC in the wildCVE-2026-735701

Critical Issabel PBX Command Execution Vulnerability Exploited in the Wild

Unauthenticated attackers exploit CVE-2026-89026 in Issabel PBX via forged JWT tokens to run OS commands; exploitation observed since September 9.

CVE-2026-89026 (CVSS v4 9.3) stems from a hard-coded HS256 JWT signing key in Issabel Framework's pbxapi/index.php, letting unauthenticated attackers forge bearer tokens and execute OS commands through the Asterisk Manager Interface originate endpoint. Issabel Framework versions before commit b97dbaf0b71c1c36f841e672b664afbeb02773bd are affected. Shadowserver Foundation first observed exploitation on September 9, 2026, and VulnCheck added the flaw to its Known Exploited Vulnerabilities database.

Cyber Security Newsupdated · 2h agofirst · 5h agoExploit / PoC in the wild 2 sourcesCVE-2026-890261

Cisco email security boxes can be rooted by... an email

Attackers actively exploit critical Cisco Secure Email Gateway flaw CVE-2026-76461, turning a malicious email into unauthenticated root access.

Cisco Secure Email Gateway appliances are being actively exploited via CVE-2026-76461, a CVSS 9.8 AsyncOS flaw requiring no authentication—a crafted email can yield root command execution with no workarounds. Cisco's PSIRT became aware of active exploitation in September; some Secure Email Cloud customers showed indicators of compromise and all cloud devices were upgraded to AsyncOS 16.5.0-780. The bug is in CISA's KEV catalog with federal agencies ordered to remediate by September 17; Shadowserver counted 400+ exposed appliances. Fixes are available in AsyncOS 15.5.5-014, 16.0.4-302, and 16.5.0-780, and attackers with root may tamper with logs to hide activity.

The Register · Securityupdated · 4h agofirst · 1d agoExploit / PoC in the wild 17 sourcesCVE-2026-76461CVE-2025-20393

CISA: Critical VMware RCE flaw now exploited by ransomware gangs

CISA warns ransomware gangs now exploit critical VMware vCenter syslog RCE CVE-2026-59310, already KEV-listed after APT compromises across 47 countries.

Broadcom patched critical directory traversal flaw CVE-2026-59310 in the vCenter Syslog server on July 29, warning of unauthenticated remote code execution. QUIRSO subsequently found 361 compromised IPs across 47 countries after a suspected APT deployed a reverse SSH tool for persistence and remote access. CISA added the flaw to its KEV catalog with a three-day patch deadline for federal agencies, and over the weekend updated it to flag active abuse by ransomware gangs. Shadowserver tracks over 450 exposed vCenter servers, and CISA has tagged 26 VMware vulnerabilities as exploited in the wild over five years, nine abused by ransomware.

BleepingComputer · 1d agoExploit / PoC in the wildCVE-2026-59310CVE-2025-60710CVE-2025-22225+2 CVEs1

MikroTik patches flaws currently being exploited to take over routers

MikroTik patches six RouterOS flaws, including the actively exploited MikroTrick SSH chain (CVE-2026-67276, CVE-2026-86060) enabling unauthenticated full router takeover.

MikroTik released patches in RouterOS 7.25 beta 3, 7.24.2, 7.23.4, and 6.49.21 for six vulnerabilities found by CERT Polska, affecting the SSH server/client, bandwidth-test service, X.509 handling, and WebFig. CVE-2026-67276, an RSA public-key validation flaw in the SSH server, lets an attacker who knows a username and key modulus authenticate as that user; CVE-2026-86060 then escalates privileges to root via special-character username handling. CERT Polska confirmed attackers are exploiting the chain to take full control of RouterOS devices with SSH exposed to the internet. Shadowserver Foundation scans show over 122,500 devices with internet-reachable SSH, concentrated in Brazil, the US, and Indonesia.

CSO Onlineupdated · 5d agofirst · 6d agoExploit / PoC in the wild 3 sourcesCVE-2026-67276CVE-2026-860602

MikroTik Patches Critical Flaws Chained to Hack Routers

MikroTik patches six RouterOS flaws; two chained as MikroTrick are actively exploited via SSH to fully compromise exposed routers.

MikroTik released patches for six RouterOS vulnerabilities, including actively exploited MikroTrick chain: CVE-2026-67276 (9.2, SSH auth bypass) and CVE-2026-86060 (9.2, privilege manipulation), plus CVE-2026-67277 (8.8). CERT Poland confirms exploitation since September 2, creating an 'ops' account from IPs 82.192.72.4 and 103.102.31.18. Fixed in RouterOS 7.25beta3, 7.24.2, 7.23.4, and 6.49.21; Shadowserver found 120,000+ SSH-exposed MikroTik devices.

SecurityWeek · 8d agoExploit / PoC in the wildCVE-2026-67276CVE-2026-67277CVE-2026-67278+3 CVEs1