What is CVE-2016-9459?

CVE-2016-9459 is a medium-severity vulnerability in Nextcloud Server, classified under Generation of Error Message Containing Sensitive Information. CVSS score: 6.1/10. Published 2017-03-28.

How severe is CVE-2016-9459?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Nextcloud Server

CVE-2016-9459

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are vulnerable to a log pollution vulnerability potentially leading to a local XSS. The download log functionality in the admin screen is delivering the log in JSON format to the end-user. The file was delivered with an attachment disposition forcing the browser to download the document. However, Firefox running on Microsoft Windows would offer the user to open the data in the browser as an HTML document. Thus any injected data in the log would be executed.

Published 2017-03-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.015 (73.1th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 73rd percentile — 73.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000

Affected products

Nextcloud Server
ownCloud
Nextcloud Server & ownCloud Before 9.0.52 9.0.4 — versions Nextcloud Server & ownCloud Server Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4

Weakness classification (CWE)

References

owncloud.org/security/advisory (Patch, Vendor Advisory)
github.com/owncloud/core/commit/b7fa2c5dc945b40bc6ed0a9a0e47c282ebf043e1 (Patch, Third Party Advisory, Issue Tracking)
github.com/owncloud/core/commit/044ee072a647636b1a17c89265c7233b35371335 (Patch, Third Party Advisory, Issue Tracking)
hackerone.com/reports/146278 (Exploit, Third Party Advisory)
github.com/owncloud/core/commit/efa35d621dc7ff975468e636a5d1c153511296dc (Patch, Third Party Advisory, Issue Tracking)
nextcloud.com/security/advisory/ (Patch, Vendor Advisory)
github.com/nextcloud/server/commit/94975af6db1551c2d23136c2ea22866a5b416070 (Patch, Third Party Advisory, Issue Tracking)
www.securityfocus.com/bid/97284 (VDB Entry, Third Party Advisory, vdb-entry)

Frequently asked questions

What is CVE-2016-9459?: CVE-2016-9459 is a medium-severity vulnerability in Nextcloud Server, classified under Generation of Error Message Containing Sensitive Information. CVSS score: 6.1/10. Published 2017-03-28.
How severe is CVE-2016-9459?: Medium severity. CVSS v3 base score is 6.1 out of 10.