high
7.5
CWE
327 400
Advisory Published
CVE Published
Advisory Published
Updated

CVE-2020-13757

First published: Wed May 27 2020(Updated: )

A flaw was found in the python-rsa package, where it does not explicitly check the ciphertext length against the key size and ignores the leading 0 bytes during the decryption of the ciphertext. This flaw allows an attacker to perform a ciphertext attack, leading to a denial of service. The highest threat from this vulnerability is to confidentiality.

Credit: cve@mitre.org

Affected SoftwareAffected VersionHow to fix
redhat/python-rsa<0:4.5-2.el7
0:4.5-2.el7
redhat/python-rsa<0:4.5-1.el7
0:4.5-1.el7
redhat/python-rsa<4.1
4.1
debian/python-rsa<=4.0-4
4.8-1
4.9-2
pip/rsa<4.1
4.1
python3-rfc3339<4.1
Red Hat Fedora=31
Red Hat Fedora=32
Ubuntu=14.04

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Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2020-13757?

    CVE-2020-13757 has been classified as a high severity vulnerability due to the potential for denial of service attacks.

  • How do I fix CVE-2020-13757?

    To fix CVE-2020-13757, upgrade the python-rsa package to version 4.1 or later.

  • Which versions of python-rsa are affected by CVE-2020-13757?

    Versions of python-rsa prior to 4.1 are affected by CVE-2020-13757.

  • Can CVE-2020-13757 be exploited remotely?

    Yes, CVE-2020-13757 can be exploited remotely, allowing attackers to execute ciphertext attacks.

  • What impact does CVE-2020-13757 have on systems using python-rsa?

    CVE-2020-13757 can lead to denial of service on systems utilizing the vulnerable python-rsa package.

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