Hackers Exploit Critical Cisco Secure Email Gateway Flaw to Execute Commands as Root
Cisco patched critical unauthenticated SQL injection CVE-2026-76461 (CVSS 9.8) in Secure Email Gateway enabling root command execution, with malicious activity already detected.
Cisco disclosed CVE-2026-76461, a critical SQL injection (CVSS 9.8) in Cisco Secure Email Gateway appliances running AsyncOS, letting unauthenticated remote attackers execute arbitrary commands as root via crafted emails containing malicious SQL statements. Cisco detected malicious activity and directly contacted Secure Email Cloud customers, indicating active exploitation. No workaround exists; fixed releases are AsyncOS 15.5.5-0141, 16.0.4-3021, and 16.5.0-780, with migration to 16.5.0-780 advised. Secure Email and Web Manager and Secure Web Appliance are not affected.
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.
Cisco Secure Email Gateway Flaw Exploited in the Wild, Enables Root Command Execution
Cisco warns CVE-2026-76461 in Secure Email Gateway AsyncOS is actively exploited, letting unauthenticated attackers run root commands via crafted emails.
Cisco disclosed CVE-2026-76461, a CVSS 9.8 flaw in AsyncOS for Cisco Secure Email Gateway caused by insufficient validation in email parsing, allowing unauthenticated remote attackers to execute arbitrary SQL statements leading to root command execution. Active exploitation began in September 2026, and CISA added the flaw to its KEV catalog, requiring FCEB agencies to patch by September 17, 2026. Fixes are available in AsyncOS 15.5.5-0141, 16.0.4-302, and 16.5.0-780, with no workarounds. Cisco also contacted Secure Email Cloud customers where malicious activity was detected, and the article separately notes large-scale credential attacks on Fortinet VPN appliances generating tens of millions of authentication failures.
Root RCE Zero-Day in Cisco Secure Email Gateway Under Active Exploitation
Cisco warns CVE-2026-76461 (CVSS 9.8), an unauthenticated root RCE in Secure Email Gateway AsyncOS, is actively exploited in the wild.
Cisco confirmed that CVE-2026-76461, a CVSS 9.8 email-parsing flaw in Secure Email Gateway AsyncOS, is being exploited in the wild since September 2026, allowing unauthenticated remote attackers to execute arbitrary commands with root privileges via crafted emails containing malicious SQL statements. All physical and virtual SEG configurations are affected; Secure Email and Web Manager and Secure Web Appliance are not. CISA added the flaw to the KEV catalog with a September 17 federal remediation deadline, and Cisco released IoCs while noting root access lets attackers remove them.
Hackers Exploit Critical Cisco Secure Email Gateway Vulnerability in the Wild to Run Malicious Code
Cisco warns attackers actively exploit zero-day CVE-2026-76461 in Secure Email Gateway, gaining unauthenticated root command execution via crafted emails.
Cisco PSIRT confirmed active in-the-wild exploitation of CVE-2026-76461 throughout September 2026, a zero-day in Secure Email Gateway AsyncOS that lets remote, unauthenticated attackers execute arbitrary commands with root privileges by sending maliciously crafted emails containing injected SQL statements. Physical appliances, virtual deployments, and Cisco Secure Email Cloud instances were affected; Cisco deployed server-side remediations for cloud tenants but on-premises admins must patch themselves. Fixes ship in AsyncOS 16.5.0-780 plus branches 16.0.4-3021 and 15.5.5-0141, and no workarounds exist.
CISA Warns of Cisco Secure Email Gateway 0-Day Vulnerability Actively Exploited in Attacks
CISA added actively exploited Cisco Secure Email Gateway SQL injection flaw CVE-2026-76461 to its KEV catalog, enabling unauthenticated root command execution.
CVE-2026-76461 is an unauthenticated SQL injection (CWE-89) in Cisco AsyncOS for Cisco Secure Email Gateway appliances, allowing remote attackers to execute arbitrary OS commands with root privileges. CISA added the flaw to the KEV catalog on September 14, 2026, requiring federal civilian agencies to apply vendor mitigations by September 17, 2026, and forensic triage under BOD 26-04. A compromised gateway could let attackers alter email security policies, access stored messages, disable logging, and pivot into enterprise networks.
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.
U.S. CISA adds Cisco Secure Email Gateway flaw to its Known Exploited Vulnerabilities catalog
CISA added actively exploited Cisco Secure Email Gateway zero-day CVE-2026-76461 (CVSS 9.8) to KEV; federal agencies must patch by September 17, 2026.
CISA added CVE-2026-76461 (CVSS 9.8), a critical zero-day in Cisco AsyncOS for Cisco Secure Email Gateway, to its Known Exploited Vulnerabilities catalog. The flaw stems from insufficient validation in email parsing, letting an unauthenticated remote attacker send a crafted email with malicious SQL statements to achieve arbitrary command execution with root privileges. Cisco confirmed active exploitation in the wild, notes no workarounds exist, and recommends checking mail_logs for suspicious SQL statements like 'COPY.*TO PROGRAM' on every cluster device. Under BOD 22-01, FCEB agencies must remediate by September 17, 2026.
Critical Cisco Secure Email Gateway zero-day gives attackers root access
Actively exploited Cisco Secure Email Gateway zero-day CVE-2026-76461 lets crafted emails trigger SQL injection and root command execution; CISA added it to KEV.
Cisco released emergency patches for CVE-2026-76461, a critical SQL injection in Secure Email Gateway (physical and virtual) caused by insufficient validation in email parsing. Sending a crafted email with malicious SQL statements can yield arbitrary command execution with root privileges. Cisco was aware of active exploitation before the fixes, and CISA added the flaw to its KEV catalog; patched AsyncOS releases are 15.5.5-0141, 16.0.4-3021, and 16.5.0-780. Because successful exploits grant root, Cisco warns logs may be tampered with and advises checking external firewall/network logs and rebuilding virtual appliances with rotated credentials.
Cisco warns customers of actively exploited zero-day in email gateways
Actively exploited Cisco Secure Email Gateway zero-day CVE-2026-76461 allows unauthenticated root command execution; CISA added it to KEV.
Cisco disclosed CVE-2026-76461, a zero-day in AsyncOS for Cisco Secure Email Gateway that was exploited before disclosure and lets unauthenticated remote attackers execute commands with root privileges on cloud and on-premises instances. CISA promptly added the flaw to its Known Exploited Vulnerabilities catalog, and Cisco has directly contacted cloud customers with indicators of compromise while deploying mitigations. Rapid7 and VulnCheck warn compromised gateways could enable silent email monitoring and internal pivoting from on-premises deployments.
Cisco Secure Email Gateway Vulnerability Exploited in Attacks (CVE-2026-76461)
Cisco Secure Email Gateway flaw CVE-2026-76461 enables root command execution via crafted email SQL injection and is actively exploited, added to CISA KEV.
Cisco disclosed critical vulnerability CVE-2026-76461 in Secure Email Gateway, caused by insufficient validation in email parsing logic, allowing arbitrary SQL statements that lead to root-level command execution. CISA added the flaw to its Known Exploited Vulnerabilities Catalog with a patch deadline of September 17, 2026. The bug affects all SEG deployments regardless of configuration, with fixed releases including 15.5.5-014, 16.0.4-302, and 16.5.0-780. Defenders can check mail_logs for anomalous 'COPY ... TO PROGRAM' SQL statements to detect compromise.
Cisco Warns of Ongoing Exploitation of Critical Email Gateway Zero-Day
Cisco Secure Email Gateway zero-day CVE-2026-76461 (CVSS 9.8) is actively exploited for root command execution; CISA added it to KEV.
Cisco disclosed critical zero-day CVE-2026-76461 (CVSS 9.8) in Secure Email Gateway, remotely exploitable without authentication via crafted emails containing malicious SQL statements, leading to arbitrary command execution with root privileges. The flaw affects physical and virtual appliances regardless of configuration and has no workarounds. Cisco PSIRT confirmed active exploitation, and CISA added the CVE to its KEV catalog on September 14 with a federal remediation deadline of September 17. Admins should review mail_logs for suspicious SQL statements such as 'COPY.*TO PROGRAM'.
CVE-2026-76461: Critical Cisco Secure Email Gateway Vulnerability Exploited in the Wild
Cisco Secure Email Gateway zero-day CVE-2026-76461 (CVSS 9.8) enables unauthenticated root command execution via crafted email; CISA added it to KEV.
CVE-2026-76461 is a critical SQL injection (CVSS 9.8) in Cisco AsyncOS for Secure Email Gateway allowing an unauthenticated remote attacker to execute arbitrary commands with root privileges by sending a specially crafted email through a vulnerable gateway. CISA added it to the KEV catalog on disclosure day, indicating zero-day exploitation, and Cisco PSIRT became aware of active exploitation in September 2026. No public PoC or attribution exists; fixed versions are 15.5.5-014, 16.0.4-302, and 16.5.0-780, and admins should check mail_logs for suspicious SQL statements like 'COPY.*TO PROGRAM'.
Cisco patches actively exploited email gateway zero-day (CVE-2026-76461)
Actively exploited zero-day SQL injection (CVE-2026-76461) in Cisco Secure Email Gateway allows unauthenticated root command execution; CISA ordered federal remediation by September 17.
Cisco confirmed attackers are exploiting zero-day CVE-2026-76461, an unauthenticated SQL injection in the email parsing logic of AsyncOS on Secure Email Gateway appliances (versions 16.5, 16.0, 15.5 and earlier) and Secure Email Cloud. Successful exploitation yields arbitrary SQL execution and root-level command execution on the underlying OS without user interaction. Cisco became aware of active exploitation in September 2025, has directly contacted affected cloud customers, and released fixed releases 15.5.5-014, 16.0.4-302, and 16.5.0-780. CISA added the flaw to its Known Exploited Vulnerabilities catalog and required federal civilian agencies to patch by September 17 and hunt for compromise.