How severe is CVE-2021-35208?

CVE-2021-35208 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-35208 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35208?

CVE-2021-35208 primarily affects Zimbra Collaboration. In total, 24 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-35208?

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

When was CVE-2021-35208 published?

CVE-2021-35208 was published on 2021-07-02 and last updated on 2026-06-17.

CVE-2021-35208

CVE-2021-35208 is a medium-severity vulnerability in Zimbra Collaboration with a CVSS 3.x base score of 5.4. 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 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (66th 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 ZmMailMsgView.js in the Calendar Invite component in Zimbra Collaboration Suite 8.8.x before 8.8.15 Patch 23. An attacker could place HTML containing executable JavaScript inside element attributes. This markup becomes unescaped, causing arbitrary markup to be injected into the document.

Frequently asked questions

What is CVE-2021-35208?: An issue was discovered in ZmMailMsgView.js in the Calendar Invite component in Zimbra Collaboration Suite 8.8.x before 8.8.15 Patch 23. An attacker could place HTML containing executable JavaScript inside element attributes. This markup becomes unescaped, causing arbitrary markup to be injected into the document.
How severe is CVE-2021-35208?: CVE-2021-35208 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-35208 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35208?: CVE-2021-35208 primarily affects Zimbra Collaboration. In total, 24 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-35208?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-35208 published?: CVE-2021-35208 was published on 2021-07-02 and last updated on 2026-06-17.

References

Affected products (24)

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:*:*:*:*:*:*

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