Threat landscape
critical exploited

Synacor Zimbra: Mehrere Schwachstellen

WID-SEC-2026-2429 · first 21.07.2026 · updated 26.10.2026 · CVSS 9,8

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What it is about

Zimbra ist eine Groupware-Lösung, die E-Mail, Kalender und Aufgabenverwaltung bietet. Ein Angreifer kann mehrere Schwachstellen in Synacor Zimbra ausnutzen, um beliebigen Programmcode auszuführen, Cross-Site-Scripting-Angriffe durchzuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen und unbefugte Aktionen durchzuführen.

Under what conditions?

The BSI does not name any particular preconditions. Exploitable remotely according to the BSI.

What can happen in the worst case

An attacker could use the vulnerability to

  • beliebigen Programmcode auszuführen
  • Cross-Site-Scripting-Angriffe durchzuführen
  • Sicherheitsmaßnahmen zu umgehen
  • vertrauliche Informationen offenzulegen
  • unbefugte Aktionen durchzuführen

Am I affected?

Affected according to the BSI:

  • Synacor Zimbra <10.1.20

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

What helps?

Update to at least:

  • Synacor Zimbra 10.1.20

Is the vulnerability already being exploited?

  • CVE-2026-73570: exploited in the wild according to CISA, in the catalogue since 21.08.2026.

Information and sources

CVE: CVE-2026-10631, CVE-2026-50054, CVE-2026-50055, CVE-2026-73570

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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