CVE-2020-36242

CRITICAL EPSS 93.1%
Published Feb 7, 20215y ago · Modified Jun 17, 20262w ago
9.1 CVSS 3.1
Critical
Find Similar
Published Feb 7, 2021 5y ago
Last Modified Jun 17, 2026 2w ago

Description

In the cryptography package before 3.3.2 for Python, certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

CVSS Details

Base Score
9.1
Exploitability
3.9
Impact
5.2
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
93.1% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 2

CWE-190 Integer Overflow or Wraparound Numeric Error
CWE-787 Out-of-bounds Write Memory Safety

Affected Products 3

VendorProductVersionRange
cryptography.iocryptography* <3.3.2
fedoraprojectfedora33any
oraclecommunications_cloud_native_core_network_function_cloud_native_environment1.10.0any

References 6

  • github.com https://github.com/pyca/cryptography/blob/master/CHANGELOG.rst
    Release NotesThird Party Advisory
  • github.com https://github.com/pyca/cryptography/compare/3.3.1...3.3.2
    PatchThird Party Advisory
  • github.com https://github.com/pyca/cryptography/issues/5615
    ExploitPatchThird Party Advisory
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L7RGQLK4J5ZQFRLKCHVVG6BKZTUQMG7E/
  • oracle.com https://www.oracle.com/security-alerts/cpuapr2022.html
    PatchThird Party Advisory
  • oracle.com https://www.oracle.com/security-alerts/cpujul2022.html
    PatchThird Party Advisory

Remediation

  • github.com https://github.com/pyca/cryptography/compare/3.3.1...3.3.2
    PatchThird Party Advisory
  • github.com https://github.com/pyca/cryptography/issues/5615
    ExploitPatchThird Party Advisory
  • oracle.com https://www.oracle.com/security-alerts/cpuapr2022.html
    PatchThird Party Advisory
  • oracle.com https://www.oracle.com/security-alerts/cpujul2022.html
    PatchThird Party Advisory