Ubuntu update for python-rsa

1) Use of a broken or risky cryptographic algorithm

EUVDB-ID: #VU28793

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-13757

CWE-ID: CWE-327 - Use of a Broken or Risky Cryptographic Algorithm

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to sensitive information on the target system.

The vulnerability exists due to the affected software does not detect ciphertext modification during decryption (prepended "0" bytes) in PKCS1_v1_5. A remote attacker gain access to sensitive information on the system.

Mitigation

Update the affected package python-rsa to the latest version.

Vulnerable software versions

Ubuntu: 14.04

python3-rsa (Ubuntu package): before 3.1.2-1ubuntu0.1+esm1

python-rsa (Ubuntu package): before 3.1.2-1ubuntu0.1+esm1

CPE2.3

• cpe:2.3:o:canonical:ubuntu:14.04:*:*:*:*:*:*:*
• cpe:2.3:a:canonical:python3-rsa_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:python-rsa_ubuntu_package:*:*:*:*:*:ubuntu:*:*

External links

https://ubuntu.com/security/notices/USN-4478-1

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.