Is CVE-2023-37580 actively exploited?

Yes. KEV Intelligence tracks CVE-2023-37580 as a known exploited vulnerability. Confidence is confirmed.

What exploitation activity has KEV Intelligence observed?

KEV Intelligence has not yet recorded sensor-observed exploitation attempts for CVE-2023-37580. Our sensors continue to monitor for activity targeting this CVE.

Which versions are affected?

Version-level data is not available; KEV Intelligence tracks Zimbra Zimbra Collaboration.

Yes. CVE-2023-37580 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2023-37580

Zimbra Collaboration Cross-Site Scripting

Zimbra / Zimbra Collaboration

View live feed Monitor via API Watch CVE

Severity: CVSS 6.1 · Medium
Confidence: Confirmed
Exploit status: Exploited in the wild
EPSS: 46.7%
First observed: —
Last observed: —

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2023-37580 is an unauthenticated vulnerability affecting Zimbra Zimbra Collaboration. Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client.

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is confirmed.

Who is affected?

Zimbra / Zimbra Collaboration.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client

Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client.

Published: 31 Jul 2023
Exploitation Reported: 27 Jul 2023
Attack vector: Remote
Complexity: Low
Privileges: None
User interaction: Required

CVE References

CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2023-37580
[oss-security] 20231117 CVE-2023-37580 (and others): XSS vulnerabilities in Zimbra Collaboration Suite openwall.com · Mailing List http://www.openwall.com/lists/oss-security/2023/11/17/2
wiki.zimbra.com/wiki/Security_Center wiki.zimbra.com · CVE Record https://wiki.zimbra.com/wiki/Security_Center
wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy wiki.zimbra.com · CVE Record https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 27 Jul 2023

Independent exploitation attestation added to the KEV Intelligence record.

Proof of concept available

Nuclei Templates

Recorded 12 Jun 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

Learn about Pro API access

Source	Added
CISA First	2023-07-27 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets: 0
User-Agents: 0

Raw values available in Pro and Enterprise.

Scanner coverage

Nuclei template detected 25 Apr 2025.

View Nuclei template

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner	Reference	Detected
Nuclei	https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2023/CVE-2023-37580.yaml	25 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

6.1 Medium

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS

46.7%

Weaknesses

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE-79

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Zimbra Collaboration Suite (ZCS) v.8.8.15 - Cross-Site Scripting

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

12 Jun 2026
Public PoC available

Public proof-of-concept code published
25 Apr 2025
Nuclei template available

Scanner coverage available
31 Jul 2023
CVE published

Vulnerability disclosed publicly
27 Jul 2023
Added to CISA KEV

Listed in the CISA Known Exploited Vulnerabilities catalog
07 Jul 2023
CVE ID reserved

Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

View Pro pricing Read API docs

Evidence confidence and provenance
First-party sensor telemetry
PoC and scanner references
Affected versions and enrichment
Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2023-37580

Free JSON includes basic KEV fields

{
  "cve_id": "CVE-2023-37580",
  "confidence": "Confirmed",
  "cvss_score": 6.1,
  "cvss_estimated": false,
  "epss_score": 0.46709,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

Early warning alerts

Get alerts on high-impact exploitation

Receive curator-selected alerts when exploitation activity warrants attention. Each alert includes the evidence and context needed to decide what requires attention now.