Summary
USN-8087-1 fixed a vulnerability in python-cryptography. This update
provides the corresponding update to Ubuntu 16.04 LTS, Ubuntu 18.04 LTS,
and Ubuntu 20.04 LTS.
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.
Fixed packages 3
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu · Pro 16.04 LTS Pro:16.04:LTS | python-cryptography | 1.2.3-1ubuntu0.3+esm3 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | python-cryptography | 2.1.4-1ubuntu1.4+esm3 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | python-cryptography | 2.8-3ubuntu0.3+esm2 |
Vulnerabilities 1
-
High 8.2
cryptography Subgroup Attack Due to Missing Subgroup Validation for SECT Curves
cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. Prior to 46.0.5, the public_key_from_numbers (or EllipticCurvePublicNumbers.public_key()), EllipticCurvePublicNumbers.public_key(), load_der_public_key() a…
References
-
report
https://ubuntu.com/security/CVE-2026-26007