What is CVE-2016-10516?

CVE-2016-10516 is a medium-severity vulnerability in Palletsprojects Werkzeug, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2017-10-23.

How severe is CVE-2016-10516?

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

XSS in Palletsprojects Werkzeug

CVE-2016-10516

Cross-site scripting (XSS) vulnerability in the render_full function in debug/tbtools.py in the debugger in Pallets Werkzeug before 0.11.11 (as used in Pallets Flask and other products) allows remote attackers to inject arbitrary web script or HTML via a field that contains an exception message.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2017-10-23 · 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: 0.020 (79.8th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 80th percentile — 79.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.020 · newest: 0.020 · change: 0.000

Affected products

Palletsprojects Werkzeug

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

blog.neargle.com/2016/09/21/flask-src-review-get-a-xss-from-debuger/ (Issue Tracking)
lists.debian.org/debian-lts-announce/2017/11/msg00037.html (mailing-list)
github.com/pallets/werkzeug/pull/1001 (Third Party Advisory)

Frequently asked questions

What is CVE-2016-10516?: CVE-2016-10516 is a medium-severity vulnerability in Palletsprojects Werkzeug, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2017-10-23.
How severe is CVE-2016-10516?: Medium severity. CVSS v3 base score is 6.1 out of 10.