How severe is CVE-2018-6882?

CVE-2018-6882 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-2018-6882 being actively exploited?

Yes. CVE-2018-6882 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-04-19, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2018-6882?

CVE-2018-6882 primarily affects Synacor Zimbra Collaboration Suite. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-6882?

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-2018-6882 have an EU (EUVD) identifier?

Yes. CVE-2018-6882 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2018-18627. It is also flagged as exploited in the EUVD (since 2022-04-19).

When was CVE-2018-6882 published?

CVE-2018-6882 was published on 2018-03-27 and last updated on 2026-06-17.

CVE-2018-6882

CVE-2018-6882 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 2022-04-19). The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 24% (98th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-04-19)
EU (EUVD) id: EUVD-2018-18627
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-04-19)
Weakness: CWE-79
Affected product: Synacor Zimbra Collaboration Suite
Published: 2018-03-27
Last modified: 2026-06-17

Description

Cross-site scripting (XSS) vulnerability in the ZmMailMsgView.getAttachmentLinkHtml function in Zimbra Collaboration Suite (ZCS) before 8.7 Patch 1 and 8.8.x before 8.8.7 might allow remote attackers to inject arbitrary web script or HTML via a Content-Location header in an email attachment.

Frequently asked questions

What is CVE-2018-6882?: Cross-site scripting (XSS) vulnerability in the ZmMailMsgView.getAttachmentLinkHtml function in Zimbra Collaboration Suite (ZCS) before 8.7 Patch 1 and 8.8.x before 8.8.7 might allow remote attackers to inject arbitrary web script or HTML via a Content-Location header in an email attachment.
How severe is CVE-2018-6882?: CVE-2018-6882 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-2018-6882 being actively exploited?: Yes. CVE-2018-6882 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-04-19, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2018-6882?: CVE-2018-6882 primarily affects Synacor Zimbra Collaboration Suite. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-6882?: 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-2018-6882 have an EU (EUVD) identifier?: Yes. CVE-2018-6882 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2018-18627. It is also flagged as exploited in the EUVD (since 2022-04-19).
When was CVE-2018-6882 published?: CVE-2018-6882 was published on 2018-03-27 and last updated on 2026-06-17.

References

Affected products (9)

cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.7.0:-:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.0:*:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.1:*:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.2:*:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.3:*:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.4:*:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.5:*:*:*:*:*:*:*
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.6:*:*:*:*:*:*:*

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