How 2 Missing Characters Nearly Compromised AWS

A massive security hole that could have given hackers total control over Amazon Web Services (AWS) was recently fixed before anyone could actually use it for harm. The discovery, made by Wiz Research, prevented what they called a “historic near miss” for the millions of businesses and people who rely on the cloud every day.

****A Two-Character Mistake****

The vulnerability, which researchers named CodeBreach, was found inside a tool called AWS CodeBuild. In technical terms, this tool is part of a supply chain, which is basically the automated series of steps that take a developer’s raw code and turn it into a finished software product. In this case, the flaw hit the AWS JavaScript SDK, a key library that acts as the engine for the AWS Console.

As we know it, the Console is the main dashboard where users manage their entire cloud presence. Because the dashboard depends on this specific library to work, a flaw here meant the entire management platform was at risk.

The root of the problem was surprisingly simple, related to two missing characters in a security filter. This filter used a search pattern (known as a Regex) to decide which code updates were safe to run, and those two missing characters meant the filter wasn’t properly anchored.

According to researchers, this allowed them to “infiltrate the build environment and leak privileged credentials.” Further probing revealed that once they had those credentials, they could have taken over the entire software repository.

****Preventing a Global Crisis****

If a malicious actor had spotted this first, they could have injected backdoor code directly into the AWS infrastructure. Wiz, which shared this research with Hackread.com, noted in the blog post that the scale of such an attack could have eclipsed the infamous SolarWinds breach.

According to researchers, they alerted Amazon to the issue on August 25, 2025. AWS acted fast, fixing the main issue within 48 hours and rolling out global security improvements shortly after. If you are a regular AWS user, you don’t need to do anything. Amazon has already handled the cleanup on its end.

Attack process explained (source: Wiz Research)

****Lessons for Developers****

While this specific fire was put out, researchers noted that these types of risks are on the rise because “one small thing can lead to an insanely large break.” This follows a similar incident from last July involving the Amazon Q extension.

To stay safe, Wiz Research suggests that anyone using CodeBuild should turn on a Pull Request Comment Approval gate. This ensures that no automated build starts until a trusted human reviews the request.