What is CVE-2016-3954?

CVE-2016-3954 is a medium-severity vulnerability in Web2py, classified under Information Disclosure. CVSS score: 5.5/10. Published 2018-02-06.

How severe is CVE-2016-3954?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Information disclosure in Web2py

CVE-2016-3954

web2py before 2.14.2 allows remote attackers to obtain the session_cookie_key value via a direct request to examples/simple_examples/status. NOTE: this issue can be leveraged by remote attackers to execute arbitrary code using CVE-2016-3957.

Vulnerability class: Information Disclosure

Published 2018-02-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.014 (71.3th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 71st percentile — 71.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

Web2py

Weakness classification (CWE)

CWE-200 — Information Disclosure

References

devco.re/blog/2017/01/03/web2py-unserialize-code-execution-CVE-2016-3957/ (Technical Description, Exploit, Third Party Advisory)
usn.ubuntu.com/4030-1/ (vendor-advisory)

Frequently asked questions

What is CVE-2016-3954?: CVE-2016-3954 is a medium-severity vulnerability in Web2py, classified under Information Disclosure. CVSS score: 5.5/10. Published 2018-02-06.
How severe is CVE-2016-3954?: Medium severity. CVSS v3 base score is 5.5 out of 10.