An issue was discovered in the character definitions of the Unicode Specification through 14.0. The specification allows an adversary to produce source code identifiers such as function names using homoglyphs that render visually identical to a target identifier. Adversaries can leverage this to inject code via adversarial identifier definitions in upstream software dependencies invoked deceptively in downstream software.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-42694
• https://cwe.mitre.org/data/definitions/1007.html
• https://trojansource.codes
• https://www.kb.cert.org/vuls/id/999008
• https://www.scyon.nl/post/trojans-in-your-source-code
• http://www.openwall.com/lists/oss-security/2021/11/01/1
• http://www.openwall.com/lists/oss-security/2021/11/01/6
• https://security.gentoo.org/glsa/202210-09
• https://www.unicode.org/reports/tr36
• https://www.unicode.org/reports/tr39
• http://www.unicode.org/versions/Unicode14.0.0