CVE-2020-13757

mediumpriority · track · 31OT risk · elevatedEPSS 0.014 · 73 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.43% (73rd) EPSS

CVSS 5 · medium

Is it mine?

15 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

Python-RSA before 4.1 ignores leading '\0' bytes during decryption of ciphertext. This could conceivably have a security-relevant impact, e.g., by helping an attacker to infer that an application uses Python-RSA, or if the length of accepted ciphertext affects application behavior (such as by causing excessive memory allocation).

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixedpython-rsa-0:4.5-1.el7.src as a component of Red Hat OpenShift Container Platform 4.5redhat_csaf
For OpenShift Container Platform 4.5 see the following documentation, which will be updated shortly for release 4.5.6, for important instructions on how to upgrade your cluster and fully apply this asynchronous errata update: https://docs.openshift.com/container-platform/4.5/release_notes/ocp-4-5-release-notes.html Details on how to access this content are available at https://docs.openshift.com/container-platform/4.5/updating/updating-cluster-cli.html.
https://access.redhat.com/errata/RHSA-2020:3453
Fixedpython2-rsa-0:4.5-1.el7.noarch as a component of Red Hat OpenShift Container Platform 4.5redhat_csaf
For OpenShift Container Platform 4.5 see the following documentation, which will be updated shortly for release 4.5.6, for important instructions on how to upgrade your cluster and fully apply this asynchronous errata update: https://docs.openshift.com/container-platform/4.5/release_notes/ocp-4-5-release-notes.html Details on how to access this content are available at https://docs.openshift.com/container-platform/4.5/updating/updating-cluster-cli.html.
https://access.redhat.com/errata/RHSA-2020:3453

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · OSV

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · Red Hat Product Security US

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-327USprimaryCWE-325USCWE-327USCWE-327US

affected products (15)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
Python Software Foundation Python RSA≤ 4.1fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 11fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 12fstec_bduRU
canonical ubuntu linux= 14.04nvdUScpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:*:*:*:*
fedoraproject fedora= 31nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
fedoraproject fedora= 32nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
python-rsa project python-rsa< 4.1nvdUScpe:2.3:a:python-rsa_project:python-rsa:*:*:*:*:*:*:*:*
PyPI rsa< 4.1osvUSpkg:pypi/rsa
jenkins-2-plugins-0:4.5.1596698303-1.el7.noarch as a component of Red Hat OpenShift Container Platform 4.5all versionsnot affectedredhat_csafUS
jenkins-2-plugins-0:4.5.1596698303-1.el7.src as a component of Red Hat OpenShift Container Platform 4.5all versionsnot affectedredhat_csafUS
python-rsa-0:4.5-1.el7.src as a component of Red Hat OpenShift Container Platform 4.5all versionsfixedredhat_csafUS
python2-rsa-0:4.5-1.el7.noarch as a component of Red Hat OpenShift Container Platform 4.5all versionsfixedredhat_csafUS

advisories (3)

Vendor and ecosystem advisories describing this.

RHSA-2020:3453Red Hat Security Advisory: OpenShift Container Platform 4.5.6 security update2020-08-18csaf · redhat_csafUS
An update for jenkins-2-plugins and python-rsa is now available for Red Hat OpenShift Container Platform 4.5. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
GHSA-537h-rv9q-vvphPython-RSA decryption of ciphertext leads to DoS2021-03-24ghsa · osvUS
Python-RSA before 4.1 ignores leading '\0' bytes during decryption of ciphertext. This could conceivably have a security-relevant impact, e.g., by helping an attacker to infer that an application uses Python-RSA, or if the length of accepted ciphertext affects application behavior (such as by causing excessive memory allocation).
PYSEC-2020-992020-06-01vendor · osvUS
Python-RSA before 4.1 ignores leading '\0' bytes during decryption of ciphertext. This could conceivably have a security-relevant impact, e.g., by helping an attacker to infer that an application uses Python-RSA, or if the length of accepted ciphertext affects application behavior (such as by causing excessive memory allocation).

also known as (7)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv nvd redhat_csaf NVD CVE.org MITRE

published 2020-06-01modified 2026-06-17

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references (27)

External citations — patches, advisories, analysis.

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