Critical severity · published Feb 7, 2021
CVE-2020-36242
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…
9.1
CVSS
6.7%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)6.7% · higher than 94% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CC
CR
Cryptography · Cryptography.io
before 3.3.2 · source: NVD
FE
Fedora · Fedoraproject
33 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-36242
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-36242
Release Notes
https://github.com/pyca/cryptography/blob/master/CHANGELOG.rst
Patch
https://github.com/pyca/cryptography/compare/3.3.1...3.3.2
Exploit
https://github.com/pyca/cryptography/issues/5615
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L7RGQLK4J5ZQFRLKCHVVG6BKZTUQMG7E/
Patch
https://www.oracle.com/security-alerts/cpuapr2022.html
Patch
https://www.oracle.com/security-alerts/cpujul2022.html
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