What is CVE-2016-9646?

CVE-2016-9646 is a medium-severity vulnerability in Ikiwiki, classified under Improper Authentication. CVSS score: 5.3/10. Published 2018-04-13.

How severe is CVE-2016-9646?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Auth bypass in Ikiwiki

CVE-2016-9646

ikiwiki before 3.20161229 incorrectly called the CGI::FormBuilder->field method (similar to the CGI->param API that led to Bugzilla's CVE-2014-1572), which can be abused to lead to commit metadata forgery.

Vulnerability class: Broken Authentication

Published 2018-04-13 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.011 (65.3th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 65th percentile — 65.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.011 · change: -0.000

Affected products

Ikiwiki — versions before 3.20161229
Debian Linux — versions 7.0, 8.0, 9.0

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

www.debian.org/security/2017/dsa-3760 (vendor-advisory, Third Party Advisory)
security-tracker.debian.org/tracker/CVE-2016-9646 (Third Party Advisory, Issue Tracking)
ikiwiki.info/security/ (Vendor Advisory)
marc.info/ (mailing-list, Third Party Advisory)

Frequently asked questions

What is CVE-2016-9646?: CVE-2016-9646 is a medium-severity vulnerability in Ikiwiki, classified under Improper Authentication. CVSS score: 5.3/10. Published 2018-04-13.
How severe is CVE-2016-9646?: Medium severity. CVSS v3 base score is 5.3 out of 10.