How severe is CVE-2018-3763?

CVE-2018-3763 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2018-3763 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-3763?

CVE-2018-3763 primarily affects Nextcloud Calendar. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-3763?

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

When was CVE-2018-3763 published?

CVE-2018-3763 was published on 2018-07-05 and last updated on 2026-06-17.

CVE-2018-3763

CVE-2018-3763 is a medium-severity vulnerability in Nextcloud Calendar with a CVSS 3.x base score of 4.8. 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 4.8)
CVSS v2: 3.5
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Nextcloud Calendar
Published: 2018-07-05
Last modified: 2026-06-17

Description

In Nextcloud Calendar before 1.5.8 and 1.6.1, a missing sanitization of search results for an autocomplete field could lead to a stored XSS requiring user-interaction. The missing sanitization only affected group names, hence malicious search results could only be crafted by privileged users like admins or group admins.

Frequently asked questions

What is CVE-2018-3763?: In Nextcloud Calendar before 1.5.8 and 1.6.1, a missing sanitization of search results for an autocomplete field could lead to a stored XSS requiring user-interaction. The missing sanitization only affected group names, hence malicious search results could only be crafted by privileged users like admins or group admins.
How severe is CVE-2018-3763?: CVE-2018-3763 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2018-3763 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-3763?: CVE-2018-3763 primarily affects Nextcloud Calendar. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-3763?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-3763 published?: CVE-2018-3763 was published on 2018-07-05 and last updated on 2026-06-17.

References

https://nextcloud.com/security/advisory/?id=nc-sa-2018-004

Affected products (2)

cpe:2.3:a:nextcloud:calendar:*:*:*:*:*:*:*:*
cpe:2.3:a:nextcloud:calendar:1.6.0:*:*:*:*:*:*:*

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