CVE-2021-22878
MEDIUMCVSS 4.8/10EPSS 1.06%
Last modified
CVE-2021-22878 is a medium-severity vulnerability rated 4.8/10 on the CVSS scale. Nextcloud Server prior to 20.0.6 is vulnerable to reflected cross-site scripting (XSS) due to lack of sanitization in `OC.Notification.show`.. EPSS estimates a 1.06% chance of exploitation in the next 30 days.
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`.
Metrics
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Nextcloud | Nextcloud Server | < 20.0.6 |
| Fedoraproject | Fedora | 34 |
References
- https://github.com/nextcloud/server/pull/25234Patch, Third Party Advisory
- https://hackerone.com/reports/896522Exploit, Issue Tracking, Third Party Advisory
- https://nextcloud.com/security/advisory/?id=NC-SA-2021-005Vendor Advisory
- https://github.com/nextcloud/server/pull/25234Patch, Third Party Advisory
- https://hackerone.com/reports/896522Exploit, Issue Tracking, Third Party Advisory
- https://nextcloud.com/security/advisory/?id=NC-SA-2021-005Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2021-22878?
Nextcloud Server prior to 20.0.6 is vulnerable to reflected cross-site scripting (XSS) due to lack of sanitization in `OC.Notification.show`.
How severe is CVE-2021-22878?
CVE-2021-22878 has a CVSS score of 4.8/10 (MEDIUM severity). The EPSS model estimates a 1.06% probability of exploitation in the next 30 days.
How do I fix CVE-2021-22878?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2021
- CVE-2021-22872Revive Adserver before 5.1.0 is vulnerable to a reflected cr…6.1
- CVE-2021-22873Revive Adserver before 5.1.0 is vulnerable to open redirects…6.1
- CVE-2021-22874Revive Adserver before 5.1.1 is vulnerable to a reflected XS…6.1
- CVE-2021-22875Revive Adserver before 5.1.1 is vulnerable to a reflected XS…6.1
- CVE-2021-22876curl 7.1.1 to and including 7.75.0 is vulnerable to an "Expo…5.3
- CVE-2021-22877A missing user check in Nextcloud prior to 20.0.6 inadverten…6.5
- CVE-2021-22879Nextcloud Desktop Client prior to 3.1.3 is vulnerable to res…8.8
- CVE-2021-2288Vulnerability in the Oracle Bills of Material product of Ora…8.1
- CVE-2021-22880The PostgreSQL adapter in Active Record before 6.1.2.1, 6.0.…7.5
- CVE-2021-22881The Host Authorization middleware in Action Pack before 6.1.…6.1
- CVE-2021-22882UniFi Protect before v1.17.1 allows an attacker to use spoof…7.5
- CVE-2021-22883Node.js before 10.24.0, 12.21.0, 14.16.0, and 15.10.0 is vul…7.5
Are you affected by CVE-2021-22878?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST