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Vulnerability record · CVE-2016-3957 · published 6 February 2018

CVE-2016-3957: Web2py deserialization of untrusted data vulnerability

WWeb2py · Web2py

The secure_load function in gluon/utils.py in web2py before 2.14.2 uses pickle.loads to deserialize session information stored in cookies, which might allow remote attackers to execute arbitrary code by leveraging knowledge of encryption_key.

9.8 CVSS 3.0 Critical EPSS 4.9% · top 8.2% CWE-502 · Deserialization of untrusted data
9.8CVSS 3.0 base score, v2 7.5
4.9%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
6References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

The secure_load function in gluon/utils.py in web2py before 2.14.2 uses pickle.loads to deserialize session information stored in cookies, which might allow remote attackers to execute arbitrary code by leveraging knowledge of encryption_key.

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://devco.re/blog/2017/01/03/web2py-unserialize-code-execution-CVE-2016-3957/ ExploitTechnical DescriptionThird Party Advisory
https://github.com/web2py/web2py/blob/R-2.14.1/gluon/utils.py#L200 Third Party Advisory
https://usn.ubuntu.com/4030-1/
https://devco.re/blog/2017/01/03/web2py-unserialize-code-execution-CVE-2016-3957/ ExploitTechnical DescriptionThird Party Advisory
https://github.com/web2py/web2py/blob/R-2.14.1/gluon/utils.py#L200 Third Party Advisory
https://usn.ubuntu.com/4030-1/

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2016-3957), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.