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TI-2020-10752 Aliases CVE-2020-13757GHSA-537h-rv9q-vvph

Python-RSA before 4.1 ignores leading '\0' bytes during decryption of ciphertext.

Priority LOW 36CWE-327Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Partial Red Hat: 2 fixed, 5 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-327.

Summary

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).

Why it matters now

EPSS 0.01421 72nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial rsa (PyPI): 4.1Red Hat: 2 advisoriesRed Hat: 2 fixed, 5 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
—rsa (PyPI)before 4.14.1Patch availableGHSA-537h-rv9q-vvph
  • — Vendor— Affected all versions Fixed in — No fix listed CNA
  • rsa (PyPI) Vendor— Affected before 4.1 Fixed in 4.1 Patch available GHSA-537h-rv9q-vvph

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:python-rsa_project:python-rsa:*:*:*:*:*:*:*:*before 4.1VulnerablePython-rsa Project
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*31VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*32VulnerableFedoraproject
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*14.04VulnerableCanonical
  • cpe:2.3:a:python-rsa_project:python-rsa:*:*:*:*:*:*:*:* Versions before 4.1 Vulnerable ·Python-rsa Project
  • cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* Versions 31 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* Versions 32 Vulnerable ·Fedoraproject
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:* Versions 14.04 Vulnerable ·Canonical

Remediation

  • Fix · GHSA-537h-rv9q-vvph rsa (PyPI) Fixed in 4.1 Advisory →

Red Hat 2 advisories

  • RHSA-2020:3541 Released 2020-08-27 · Red Hat rating Important
    OpenShift Container Platform 3.11 security update
    • Red Hat OpenShift Container Platform 3.11 jenkins-2-plugins-3.11.1597310986-1.el7, jenkins-2.235.2.1597220898-1.el7, openshift-ansible-3.11.272-1.git.0.79ab6e9.el7 +6
  • RHSA-2020:3453 Released 2020-08-18 · Red Hat rating Important
    OpenShift Container Platform 4.5.6 security update
    • Red Hat OpenShift Container Platform 4.5 jenkins-2-plugins-4.5.1596698303-1.el7, python-rsa-4.5-1.el7, python2-rsa-4.5-1.el7

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Ceph Storage 4AffectedNo fix yet
Red Hat OpenStack Platform 13 (Queens)AffectedNo fix planned: Will not fix
Red Hat OpenStack Platform 15 (Stein)AffectedNo fix planned: Will not fix
Red Hat OpenStack Platform 16 (Train)AffectedNo fix planned: Will not fix
Red Hat Quay 3AffectedNo fix yet
Red Hat OpenShift Container Platform 3.11Fixed RHSA-2020:3541
Red Hat OpenShift Container Platform 4.5Fixed RHSA-2020:3453
Not affected: 2 products
  • Red Hat OpenShift Container Platform 3.11
  • Red Hat OpenShift Container Platform 4.5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-13757
  2. 2026-10-03 Alias added: GHSA-537h-rv9q-vvph

References

Exploit 1

Advisory 5

Other 5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences