What’s Vulnerable › Vulnerabilities

CVE-2016-3953

• Severity: critical (CVSS 9.8 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2018-02-06 · updated 2026-06-17
• Weakness: CWE-798

Description

The sample web application in web2py before 2.14.2 might allow remote attackers to execute arbitrary code via vectors involving use of a hardcoded encryption key when calling the session.connect function.

Affected products

• web2py: before 2.14.2 — fixed in 2.14.2

How to fix

Upgrade to a fixed version: web2py 2.14.2. Check the vendor advisory for mitigations.

References

• https://devco.re/blog/2017/01/03/web2py-unserialize-code-execution-CVE-2016-3957/
• https://github.com/web2py/web2py/blob/R-2.14.1/applications/examples/models/session.py
• https://usn.ubuntu.com/4030-1/
• https://devco.re/blog/2017/01/03/web2py-unserialize-code-execution-CVE-2016-3957/
• https://github.com/web2py/web2py/blob/R-2.14.1/applications/examples/models/session.py
• https://usn.ubuntu.com/4030-1/

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