Improper Restriction of Excessive Authentication Attempts in py-bcrypt
The py-bcrypt module before 0.3 for Python does not properly handle concurrent memory access, which allows attackers to bypass authentication via multiple authentication requests, which trigger the password hash to be overwritten.
Affected software
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| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | py-bcrypt | < 0.3 | 0.3 |
References
- http://lists.fedoraproject.org/pipermail/package-announce/2013-April/101382.html
- https://exchange.xforce.ibmcloud.com/vulnerabilities/83039
- http://lists.fedoraproject.org/pipermail/package-announce/2013-April/101387.html
- http://www.openwall.com/lists/oss-security/2013/03/26/2
- http://www.securityfocus.com/bid/58702
- https://github.com/advisories/GHSA-r838-q6jp-58xx
- https://nvd.nist.gov/vuln/detail/CVE-2013-1895
- https://github.com/grnet/python-bcrypt
- https://github.com/pypa/advisory-database/tree/main/vulns/py-bcrypt/PYSEC-2020-249.yaml
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N- Weakness (CWE)
CWE-307- Platform
- Python (PyPI)
- Package
py-bcrypt- Disclosed
- 28.01.2020
- Updated
- 11.10.2026 11:20
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2020-249 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-r838-q6jp-58xx - CC BY 4.0
Vulnerability history: py-bcrypt
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
This is the only known vulnerability of this package.
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