CVE-2021-22878

Public Exploit

Description

Nextcloud Server prior to 20.0.6 is vulnerable to reflected cross-site scripting (XSS) due to lack of sanitization in `OC.Notification.show`.

Category

4.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.37%
Vendor Advisory fedoraproject.org Vendor Advisory nextcloud.com
Affected: n/a Nextcloud Server
Published at:
Updated at:

References

Link Tags
https://hackerone.com/reports/896522 issue tracking exploit third party advisory
https://nextcloud.com/security/advisory/?id=NC-SA-2021-005 vendor advisory
https://github.com/nextcloud/server/pull/25234 third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L6BO6P6MP2MOWA6PZRXX32PLWPXN5O4S/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-22878?
CVE-2021-22878 has been scored as a medium severity vulnerability.
How to fix CVE-2021-22878?
To fix CVE-2021-22878, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-22878 being actively exploited in the wild?
It is possible that CVE-2021-22878 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-22878?
CVE-2021-22878 affects n/a Nextcloud Server.
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