CVE-2020-25659

Publication date 28 October 2020

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

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.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
python-cryptography	20.10 groovy	Fixed 3.0-1ubuntu0.1
	20.04 LTS focal	Fixed 2.8-3ubuntu0.1
	18.04 LTS bionic	Fixed 2.1.4-1ubuntu1.4
	16.04 LTS xenial	Fixed 1.2.3-1ubuntu0.3
	14.04 LTS trusty	Not in release

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
python-cryptography	Upstream: 58494b4

Severity score breakdown

Parameter	Value
Base score	5.9 · Medium
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	None
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

References

Related Ubuntu Security Notices (USN)

USN-4613-1
python-cryptography vulnerability
3 November 2020