Nextcloud · disclosed reports
Injection and Smuggling
12 disclosed reports · $1,100 paid
Every dot is a report; the named ones are the most upvoted. Bright dots were paid a bounty. Reports open on HackerOne.
Open Nextcloud on HackerOne- reports
- 12
- paid a bounty
- 2
Every one of the 12 is a mark on the map. Named now: 1 to 12, most upvoted first.
- Nextcloud Desktop Client RCE via malicious URI schemes
- position: fixed !important bypasses CSS sanitizer's fixed-position mitigation, enabling full-viewport phishing overlays.
- xmlrpc.php &wp-cron.php files are enabled, and will used for (DDOS),(DOS) and broutforce users attack.
- Unquoted body background attribute enables CSS injection that bypasses remote image blocking
- SMTP Command Injection in Appointment Emails via Newlines
- Improper handling of request URLs in nextcloud/guests allows guest users to bypass app allowlist
- SMTP Command Injection in iCalendar Attachments to Emails via Newlines
- Non-admin users can trigger writes to memcached by entering a malicious server as a share URL
- Control character filtering misses leading and trailing whitespace in file and folder names
- XSS in Desktop Client in call notification popup
- XSS in Desktop Client via user status and information
- Content spoofing on https://surveyserver.nextcloud.com
paid a bounty
Zoom in on the map and the dots under the middle of it are named where they are.
Data as of 2026-11-14. CVE List through 2026-11-14 · EPSS of 2026-11-13 · CISA KEV checked 2026-11-14. Sources: the CVE List, CISA KEV, EPSS, NVD, nuclei templates and public bug bounty data.