Explore top 10 tips to secure your open-source projects now. Read More

×
Alerts This Week
Warning Icon 1 578
Alerts This Week
Warning Icon 1 578

Ubuntu 25.10 python-cryptography Major ECC Flaw Mitigation USN-8087-3

ubuntu
Calendar Grey March 16, 2026
Dist Ubuntu Esm H88
A regression in python-cryptography affects Ubuntu releases. Update to fix ECC algorithm handling issue.
USN-8087-1 introduced a regression in python-cryptography

Summary

USN-8087-1 introduced a regression in python-cryptography

Software Description:

- python-cryptography: Cryptography Python library

Details:

USN-8087-1 fixed a vulnerability in python-cryptography. The update caused

a regression when using ECC algorithms with certain software. This update

fixes the problem.

We apologize for the inconvenience.

Original advisory details:

It was discovered that python-cryptography incorrectly handled subgroup

validation for SECT curves. A remote attacker could use this issue to

perform a subgroup attack and possibly recover the least significant bits

of private keys.

Topics%20covered

Topics Covered

security advisory critical Ubuntu regression python-cryptography ecc attack

Update Instructions

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 25.10
  python3-cryptography            43.0.0-1ubuntu1.2

Ubuntu 24.04 LTS
  python3-cryptography            41.0.7-4ubuntu0.4

Ubuntu 22.04 LTS
  python3-cryptography            3.4.8-1ubuntu2.4

In general, a standard system update will make all the necessary changes.

References

https://ubuntu.com/security/notices/USN-8087-2

https://ubuntu.com/security/notices/USN-8087-1

https://launchpad.net/bugs/2144373

Severity
critical
Lowest
Low
Medium
High
Critical

Ubuntu Security Notice USN-8087-2

Topics%20covered

Topics Covered

security advisory critical Ubuntu regression python-cryptography ecc attack

Package Information

https://launchpad.net/ubuntu/+source/python-cryptography/43.0.0-1ubuntu1.2
https://launchpad.net/ubuntu/+source/python-cryptography/41.0.7-4ubuntu0.4
https://launchpad.net/ubuntu/+source/python-cryptography/3.4.8-1ubuntu2.4

Get the latest News and Insights

Get the latest Linux and open source security news straight to your inbox.