CVE-2023-37580: Synacor Zimbra Collaboration Suite (ZCS) · n/a
Affects Synacor Zimbra Collaboration Suite (ZCS)Source CVE Database V5
Exploited in the wild · KEV due 17 Aug 2023 · public detection template (Nuclei) · 49% EPSS : upgrade to 8.8.15 now.
Data as of 26 Oct 2026, 06:26 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else.
- EPSS
- 49.0% chance of exploitation in 30 days – higher than 98% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 8.8.15
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 31 Jul 2023
Detectable: evidence found.
nuclei template: Zimbra Collaboration Suite (ZCS) v.8.8.15 - Cross-Site Scripting
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: evidence found.
Listed in CISA KEV 4 days before disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by mitre
, 24 days before disclosure
Added to CISA KEV (opens in a new tab)
exploitation confirmed
, 4 days before disclosure
CVE published
on cve.org
, t = 0
KEV remediation due
US federal deadline
, 17 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Upgrade Synacor Zimbra Collaboration Suite (ZCS) to 8.8.15.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Synacor Zimbra Collaboration Suite (ZCS) | Affected
| Fixed in
|
Description
Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client.