How severe is CVE-2020-18984?

CVE-2020-18984 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-2020-18984 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-18984?

CVE-2020-18984 affects Synacor Zimbra Collaboration Suite. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-18984?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-18984 published?

CVE-2020-18984 was published on 2021-12-15 and last updated on 2026-06-17.

CVE-2020-18984

CVE-2020-18984 is a medium-severity vulnerability in Synacor Zimbra Collaboration Suite with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. 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: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Synacor Zimbra Collaboration Suite
Published: 2021-12-15
Last modified: 2026-06-17

Description

A reflected cross-site scripting (XSS) vulnerability in the zimbraAdmin/public/secureRequest.jsp component of Zimbra Collaboration 8.8.12 allows unauthenticated attackers to execute arbitrary web scripts or HTML via a host header injection.

Frequently asked questions

What is CVE-2020-18984?: A reflected cross-site scripting (XSS) vulnerability in the zimbraAdmin/public/secureRequest.jsp component of Zimbra Collaboration 8.8.12 allows unauthenticated attackers to execute arbitrary web scripts or HTML via a host header injection.
How severe is CVE-2020-18984?: CVE-2020-18984 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-2020-18984 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-18984?: CVE-2020-18984 affects Synacor Zimbra Collaboration Suite. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-18984?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-18984 published?: CVE-2020-18984 was published on 2021-12-15 and last updated on 2026-06-17.

References

https://github.com/buxu/bug/issues/2

Affected products (1)

cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.12:-:*:*:*:*:*:*

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