CVE-2016-1494 Python RSA allows attackers to spoof signatures

Medium 5.3 Published 13 Jan 2016 Updated 5 Aug 2024

Attackers can spoof RSA signatures using crafted padding with small public exponents, bypassing signature verification in the Python-RSA library.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2016-1494?

CVE-2016-1494 is a medium-severity vulnerability in Fedoraproject Fedora, published on 13 Jan 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

The verify function in the RSA package for Python (Python-RSA) before 3.3 allows attackers to spoof signatures with a small public exponent via crafted signature padding, aka a BERserk attack.

Weakness: CWE-20

Which versions are affected by CVE-2016-1494?

3 open source packages ship an affected version, including rsa. It affects 4 products.

Package	Affected	Fixed in
`rsa` PyPI	All versions	`3.3`
`rsa` PyPI	All versions	`3.3`
`rsa` PyPI	All versions	`3.3`

Linux distribution packages (1)

python-rsa SUSE:Linux Enterprise Module for Public Cloud 12 All versions 3.1.4-11.1

Products include Fedoraproject Fedora, Opensuse Leap, Opensuse Opensuse, Python Rsa.

How do I fix CVE-2016-1494?

Upgrade rsa to 3.3 or later.

Is CVE-2016-1494 being exploited?

There is no known exploitation of CVE-2016-1494 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

All Fedoraproject Fedora vulnerabilities

Sources

Also known as DEBIAN-CVE-2016-1494, GHSA-8rjr-6qq5-pj9p, MGASA-2016-0011, PYSEC-2016-10, SUSE-SU-2016:0107-1, UBUNTU-CVE-2016-1494.