Home Cyber Security News A Python Vulnerability Could Allow Remote Code Execution Attacks

A Python Vulnerability Could Allow Remote Code Execution Attacks

by Abeerah Hashim
Rocket.Chat app vulnerabilities

A serious security vulnerability affected the Python language that could potentially lead to remote code execution attacks. Together with this, the Python Software Foundation (PSF) has fixed one more bug with their latest updates.

Python Vulnerability Triggering RCE Attacks

Reportedly, two different security vulnerabilities affected the existing Python releases leading to serious consequences.

One of these, CVE-2021-3177, is a buffer overflow vulnerability that could technically lead to remote code execution in Python applications. According to the vulnerability description,

Python 3.x through 3.9.1 has a buffer overflow in PyCArg_repr in _ctypes/callproc.c, which may lead to remote code execution in certain Python applications that accept floating-point numbers as untrusted input, as demonstrated by a 1e300 argument to c_double.from_param. This occurs because sprintf is used unsafely.

However, Python Software Foundation (PSF), in its blog post, states that this bug may not exactly trigger RCE in practical exploitation because successful exploitation requires fulfilling numerous other conditions. Yet, this could still lead to denial-of-service attacks.

Backing this observation, RedHat has also stated the same in their advisory.

Applications that use ctypes without carefully validating the input passed to it may be vulnerable to this flaw, which would allow an attacker to overflow a buffer on the stack and crash the application. The highest threat from this vulnerability is to system availability.

Alongside this one, a web cache poisoning vulnerability, CVE-2021-23336, also affected the language.

PSF Released The Fixes

PSF has recently addressed both the bugs with the release of Python 3.8.8 and 3.9.2. They had to expedite the release following the pressure from the users asking for a security fix to CVE-2021-3177.

This took us somewhat by surprise since we believed security content is cherry-picked by downstream distributors from source either way, and the RC releases provide installers for everybody else interested in upgrading in the meantime. It turns out that release candidates are mostly invisible to the community and in many cases cannot be used due to upgrade processes which users have in place.

Anyhow, the users should now upgrade to the latest Python versions to get the security fixes.

As for future releases, PSF has confirmed that the final release of Python 3.8 will arrive in May 2021. Whereas, Python 3.9.3 will arrive in May 2021.

You may also like

Latest Hacking News

Privacy Preference Center


The __cfduid cookie is used to identify individual clients behind a shared IP address and apply security settings on a per-client basis.

cookie_notice_accepted and gdpr[allowed_cookies] are used to identify the choices made from the user regarding cookie consent.

For example, if a visitor is in a coffee shop where there may be several infected machines, but the specific visitor's machine is trusted (for example, because they completed a challenge within your Challenge Passage period), the cookie allows Cloudflare to identify that client and not challenge them again. It does not correspond to any user ID in your web application, and does not store any personally identifiable information.

__cfduid, cookie_notice_accepted, gdpr[allowed_cookies]


DoubleClick by Google refers to the DoubleClick Digital Marketing platform which is a separate division within Google. This is Google’s most advanced advertising tools set, which includes five interconnected platform components.

DoubleClick Campaign Manager: the ad-serving platform, called an Ad Server, that delivers ads to your customers and measures all online advertising, even across screens and channels.

DoubleClick Bid Manager – the programmatic bidding platform for bidding on high-quality ad inventory from more than 47 ad marketplaces including Google Display Network.

DoubleClick Ad Exchange: the world’s largest ad marketplace for purchasing display, video, mobile, Search and even Facebook inventory.

DoubleClick Search: is more powerful than AdWords and used for purchasing search ads across Google, Yahoo, and Bing.

DoubleClick Creative Solutions: for designing, delivering and measuring rich media (video) ads, interactive and expandable ads.



The _ga is asssociated with Google Universal Analytics - which is a significant update to Google's more commonly used analytics service. This cookie is used to distinguish unique users by assigning a randomly generated number as a client identifier. It is included in each page request in a site and used to calculate visitor, session and campaign data for the sites analytics reports. By default it is set to expire after 2 years, although this is customisable by website owners.

The _gat global object is used to create and retrieve tracker objects, from which all other methods are invoked. Therefore the methods in this list should be run only off a tracker object created using the _gat global variable. All other methods should be called using the _gaq global object for asynchronous tracking.

_gid works as a user navigates between web pages, they can use the gtag.js tagging library to record information about the page the user has seen (for example, the page's URL) in Google Analytics. The gtag.js tagging library uses HTTP Cookies to "remember" the user's previous interactions with the web pages.

_ga, _gat, _gid