Threat landscape
high exploited

Cisco Secure Email Gateway: Mehrere Schwachstellen

WID-SEC-2026-3353 · first 15.09.2026 · updated 15.09.2026 · CVSS 9,8

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What it is about

Das Cisco Secure Email Gateway ist eine Sicherheitslösung zum Schutz der E-Mail Kommunikation. Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Cisco Secure Email Gateway ausnutzen, um beliebigen Code auszuführen – einschließlich der Ausführung von Code mit Root-Rechten –, Sicherheitsmaßnahmen zu umgehen, Daten offenzulegen oder zu manipulieren oder Denial-of-Service-Zustände herbeizuführen.

Under what conditions?

Over the network and without logging in. This is the most dangerous combination: attackers can scan reachable devices automatically.

What can happen in the worst case

An attacker could use the vulnerability to

  • beliebigen Code auszuführen – einschließlich der Ausführung von Code mit Root-Rechten –
  • Sicherheitsmaßnahmen zu umgehen
  • Daten offenzulegen oder zu manipulieren oder Denial-of-Service-Zustände herbeizuführen

Am I affected?

Affected according to the BSI:

  • Cisco Secure Email Gateway AsyncOS <16.5.0-780
  • Cisco Secure Email Gateway AsyncOS <16.0.4-302
  • Cisco Secure Email Gateway AsyncOS <15.5.5-014
  • Cisco Secure Email Gateway <15.5.5-014
  • Cisco Secure Email Gateway <16.5.0-780

The installed version is usually shown under “Help → About” or in the device’s admin interface.

What helps?

Update to at least:

  • Cisco Secure Email Gateway AsyncOS 16.5.0-780
  • Cisco Secure Email Gateway AsyncOS 16.0.4-302
  • Cisco Secure Email Gateway AsyncOS 15.5.5-014
  • Cisco Secure Email Gateway 15.5.5-014
  • Cisco Secure Email Gateway 16.5.0-780

Is the vulnerability already being exploited?

  • CVE-2026-76461: exploited in the wild according to CISA, in the catalogue since 14.09.2026.

Information and sources

CVE: CVE-2026-20353, CVE-2026-76440, CVE-2026-76441, CVE-2026-76442, CVE-2026-76443, CVE-2026-76461

Source: BSI warning and information service (CERT-Bund); CISA. The assessment of the conditions is my reading of the BSI text; the external pages are in their original language.

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