How severe is CVE-2023-37580?

CVE-2023-37580 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2023-37580 being actively exploited?

Yes. CVE-2023-37580 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-07-27, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2023-37580?

CVE-2023-37580 primarily affects Synacor Zimbra Collaboration Suite. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-37580?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2023-37580 have an EU (EUVD) identifier?

Yes. CVE-2023-37580 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-41465. It is also flagged as exploited in the EUVD (since 2023-07-27).

When was CVE-2023-37580 published?

CVE-2023-37580 was published on 2023-07-31 and last updated on 2026-06-17.

CVE-2023-37580

CVE-2023-37580 is a medium-severity vulnerability in Synacor Zimbra Collaboration Suite with a CVSS 3.x base score of 6.1. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2023-07-27). The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
EPSS exploit prediction: 59% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2023-07-27)
EU (EUVD) id: EUVD-2023-41465
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2023-07-27)
Weakness: CWE-79
Affected product: Synacor Zimbra Collaboration Suite
Published: 2023-07-31
Last modified: 2026-06-17

Description

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

Frequently asked questions

What is CVE-2023-37580?: Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client.
How severe is CVE-2023-37580?: CVE-2023-37580 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2023-37580 being actively exploited?: Yes. CVE-2023-37580 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-07-27, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2023-37580?: CVE-2023-37580 primarily affects Synacor Zimbra Collaboration Suite. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-37580?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2023-37580 have an EU (EUVD) identifier?: Yes. CVE-2023-37580 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-41465. It is also flagged as exploited in the EUVD (since 2023-07-27).
When was CVE-2023-37580 published?: CVE-2023-37580 was published on 2023-07-31 and last updated on 2026-06-17.

References

Affected products (14)

cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p11:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p26:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p3:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p30:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p31:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p32:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p33:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p34:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p35:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p37:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p38:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p40:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p5:*:*:*:*:*:*

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