CVE-2020-25659

Name: CVE-2020-25659
Creator: NVD / NIST
Published: 2021-01-11T16:15:15.04+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.9/10EPSS 2.45%

Last modified Jun 17, 2026

CVE-2020-25659 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. python-cryptography 3.2 is vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.. EPSS estimates a 2.45% chance of exploitation in the next 30 days.

Description

python-cryptography 3.2 is vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Metrics

CVSS 3.1

5.9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

2.45%

82.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-385

Affected Software

Vendor	Product	Versions
Cryptography.Io	Cryptography	3.2
Oracle	Communications Cloud Native Core Network Function Cloud Native Environment	1.10.0

References

https://github.com/pyca/cryptography/pull/5507/commits/ce1bef6f1ee06ac497ca0c837fbd1c7ef6c2472bPatch, Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2022.htmlPatch, Third Party Advisory
https://github.com/pyca/cryptography/pull/5507/commits/ce1bef6f1ee06ac497ca0c837fbd1c7ef6c2472bPatch, Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2022.htmlPatch, Third Party Advisory

Timeline

Published: Jan 11, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-25659?

python-cryptography 3.2 is vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

How severe is CVE-2020-25659?

CVE-2020-25659 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 2.45% probability of exploitation in the next 30 days.

How do I fix CVE-2020-25659?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-25659?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST