What is CVE-2016-9955?

CVE-2016-9955 is a medium-severity vulnerability in Simplesamlphp, classified under Improper Input Validation. CVSS score: 6.3/10. Published 2017-02-17.

How severe is CVE-2016-9955?

Medium severity. CVSS v3 base score is 6.3 out of 10.

Improper input validation in Simplesamlphp

CVE-2016-9955

The SimpleSAML_XML_Validator class constructor in SimpleSAMLphp before 1.14.11 might allow remote attackers to spoof signatures on SAML 1 responses or possibly cause a denial of service (memory consumption) by leveraging improper conversion of return values to boolean.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2017-02-17 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.0/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H.

EPSS exploit prediction

EPSS: 0.012 (66.5th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 66th percentile — 66.5% 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: 0.012 · change: +0.000

Affected products

Simplesamlphp
Debian Linux — versions 7.0

Weakness classification (CWE)

CWE-20 — Improper Input Validation

References

simplesamlphp.org/security/201612-02 (Vendor Advisory)
www.securityfocus.com/bid/94946 (VDB Entry, Third Party Advisory, vdb-entry)
lists.debian.org/debian-lts-announce/2018/03/msg00001.html (mailing-list, Third Party Advisory)

Frequently asked questions

What is CVE-2016-9955?: CVE-2016-9955 is a medium-severity vulnerability in Simplesamlphp, classified under Improper Input Validation. CVSS score: 6.3/10. Published 2017-02-17.
How severe is CVE-2016-9955?: Medium severity. CVSS v3 base score is 6.3 out of 10.