highclosedpatched
Synacor Zimbra Collaboration Suite (ZCS): Zimbra Collaboration Suite (ZCS) OS Command Injection Vulnerability
› Synacor Zimbra Collaboration Suite (ZCS)
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- started
- Aug 21, 2026
- closed
- Aug 21, 2026
- CVEs
- 1
- sources
- 3
## summary
Zimbra Collaboration Suite (ZCS) contains an OS command injection vulnerability which could allow an unauthenticated attacker to send specially crafted SMTP requests that may result in execution of arbitrary operating system commands as the Zimbra user. Added to CISA KEV on 2026-08-21.
severity: Actively exploited (CISA KEV)
## cve ids[1]
## affected
- See vendor advisory / CISA notes (versions not always listed in KEV feed)
## fixed in
- See vendor advisory linked in sources
## timeline[1]
CISA added CVE-2026-73570 to the KEV catalog (due 2026-08-24).
## advisories[2]
## news & write-ups[1]
## notes & caveats
Derived from CISA KEV JSON feed catalogVersion 2026.10.21. Exact affected/fixed version strings are not always in the KEV record — verify against the vendor advisory URL. startedAt uses dateAdded (exploitation may have begun earlier).
