Critical 9.1Published Feb 7, 2021

CVE-2020-36242In 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 demonstrate…

Updated under an hour ago (Nov 2, 2026, 1:40 AM ET)

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It affects cryptography.io cryptography and 2 other products. Add what you run to find out whether that includes you.

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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: 9.1 CRITICAL (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Weakness (CWE): CWE-190, CWE-787
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Modified
Record last updated: Jun 16, 2026
First seen by InfoSec Signals: Nov 1, 2026

Affected products

Affected products

cryptography.io cryptography cryptography.io:cryptography	before 3.3.2	NVD
fedoraproject fedora fedoraproject:fedora	33	NVD
oracle communications_cloud_native_core_network_function_cloud_native_environment oracle:communications_cloud_native_core_network_function_cloud_native_environment	1.10.0	NVD

References

References

https://github.com/pyca/cryptography/blob/master/CHANGELOG.rst	release-notes, third-party-advisory
https://github.com/pyca/cryptography/compare/3.3.1...3.3.2	patch, third-party-advisory
https://github.com/pyca/cryptography/issues/5615	exploit, patch, third-party-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L7RGQLK4J5ZQFRLKCHVVG6BKZTUQMG7E/
https://www.oracle.com/security-alerts/cpuapr2022.html	patch, third-party-advisory
https://www.oracle.com/security-alerts/cpujul2022.html	patch, third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.