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TH16102

Detected presence of files containing bidirectional Unicode control characters.

priorityCI/CD statusseverityeffortSAFE levelSAFE assessment
passlowhighNoneNone

About the issue​

Unicode is a text encoding standard designed to support the use of text written in all of the major languages and writing systems. While most languages are written from left to right, some are written in alternative directions. To accommodate encoding text written in such languages, the Unicode standard includes a number of special characters that allow the text direction to be specified. However, changing text direction can have adverse effects on how the encoded text is displayed and interpreted. For this reason, bidirectional Unicode control characters are commonly abused by malicious actors as a means of bypassing security solutions and avoiding detection. While presence of special Unicode characters does not imply malicious intent, all of its uses in a software package should be documented and approved. One example of acceptable use for these special characters is in script files that parse, validate, and transform Unicode-encoded text.

How to resolve the issue​

  • Investigate reported detections as indicators of software tampering.
  • Consult Mitre ATT&CK documentation: T1036.002 - Masquerading: Right-to-Left Override.
  • Consult publicly available materials on the Trojan Source vulnerability.

Incidence statistics​

ReversingLabs periodically collects and analyzes the contents of popular software package repositories for threat research purposes. Analysis results are used to calculate incidence statistics for issues (policy violations) that Spectra Assure can detect in software packages.

This section is updated when new data becomes available.

Total amount of packages analyzed

  • RubyGems: 183K
  • Nuget: 644K
  • PyPi: 628K
  • NPM: 3.72M

Total detections per repository

For every repository, the chart shows the number of packages that triggered the software assurance policy. In other words, it shows how many packages in each package repository were found to have the specific issue described on this page. This information helps you understand how common the issue is across different software communities.

If a repository is absent from the chart, that means none of the packages in that repository triggered this policy during analysis, or the policy was not used during analysis.

Distribution of total detections by project popularity

For every repository, the chart shows how many of the total detections belong to the Top 100 (1-100), Top 1000 (101-1000) and Top 10 000 (1001-10 000) most downloaded projects. This information helps you understand the impact of the issue within each community, making it clearer when the issue affects the most popular projects.

If the chart shows zero values for all of the top project groups, that means all detections were in unranked projects (lower than 10 000 on the list of most downloaded projects).