Is It On KEV?

Synacor Zimbra Collaboration Suite (ZCS)

YES - ON THE CISA KEV LIST
CVE-2023-37580

Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability

CISA catalog due date2023-08-17
overdue since 2023-08-17
EPSS exploit probability (next 30 days)49.1% · 99percentile
From CVE publication to KEV listing-4 days (2023-07-31 → 2023-07-27)
Remediation window (KEV listing to due date)21 days
Days on the KEV list1203 days
Date added to KEV2023-07-27
Known ransomware campaign useUnknown
VendorSynacor
ProductZimbra Collaboration Suite (ZCS)
Weaknesses (CWE)CWE-79

Synacor: 19 entries (1.1% of all KEV entries are from this vendor); 5 added in 2026.

BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.

Your BOD 26-04 window (SSVC tier helper)

Your remediation window ends:

Description

Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability impacting the confidentiality and integrity of data.

Required action (CISA)

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Notes

https://wiki.zimbra.com/wiki/Security_Center ; https://nvd.nist.gov/vuln/detail/CVE-2023-37580

References

Other KEV entries for this vendor: Synacor

Synacor - Vendors with KEV entries

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