How severe is CVE-2021-35207?

CVE-2021-35207 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-2021-35207 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35207?

CVE-2021-35207 primarily affects Zimbra Collaboration. In total, 40 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-35207?

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

When was CVE-2021-35207 published?

CVE-2021-35207 was published on 2021-07-02 and last updated on 2026-06-17.

CVE-2021-35207

CVE-2021-35207 is a medium-severity vulnerability in Zimbra Collaboration 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: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Zimbra Collaboration
Published: 2021-07-02
Last modified: 2026-06-17

Description

An issue was discovered in Zimbra Collaboration Suite 8.8 before 8.8.15 Patch 23 and 9.0 before 9.0.0 Patch 16. An XSS vulnerability exists in the login component of Zimbra Web Client, in which an attacker can execute arbitrary JavaScript by adding executable JavaScript to the loginErrorCode parameter of the login url.

Frequently asked questions

What is CVE-2021-35207?: An issue was discovered in Zimbra Collaboration Suite 8.8 before 8.8.15 Patch 23 and 9.0 before 9.0.0 Patch 16. An XSS vulnerability exists in the login component of Zimbra Web Client, in which an attacker can execute arbitrary JavaScript by adding executable JavaScript to the loginErrorCode parameter of the login url.
How severe is CVE-2021-35207?: CVE-2021-35207 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-2021-35207 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35207?: CVE-2021-35207 primarily affects Zimbra Collaboration. In total, 40 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-35207?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-35207 published?: CVE-2021-35207 was published on 2021-07-02 and last updated on 2026-06-17.

References

Affected products (40)

cpe:2.3:a:zimbra:collaboration:*:*:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:-:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p1:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p10:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p11:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p12:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p13:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p14:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p15:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p16:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p17:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p18:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p19:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p2:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p20:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p21:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p22:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p3:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p4:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p5:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p6:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p7:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p8:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:8.8.15:p9:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:-:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p1:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p10:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p11:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p12:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p13:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p14:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p15:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p2:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p3:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p4:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p5:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p6:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p7:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p8:*:*:*:*:*:*
cpe:2.3:a:zimbra:collaboration:9.0.0:p9:*:*:*:*:*:*

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