CVE-2021-42694

A flaw was found in the way Unicode standards are implemented in the context of development environments, which have specialized requirements for rendering text. Homoglyphs are different Unicode characters that, to the naked eye, look the same. An attacker could use homoglyphs to deceive a human reviewer by creating a malicious patch containing functions that look similar to standard library functions, such as print, but replace one character with a homoglyph. This function can then be defined in an upstream dependency to launch source code-related attacks.

The vulnerability is classified as moderate severity because it relies on social engineering and visual deception rather than exploiting a technical flaw in the software itself. While homoglyph-based attacks can deceive human reviewers, the impact is limited to cases where the code is not adequately reviewed or where automated tools fail to detect suspicious Unicode characters. Unlike higher-severity vulnerabilities, which may allow direct exploitation of system resources or escalation of privileges, this issue primarily targets code readability and review processes.

Additionally, it is important to note that this vulnerability does not affect Red Hat products, as it arises from the broader issue of Unicode handling in development environments rather than a flaw in Red Hat's implementations.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.