LIVE NEWSROOM · --:-- · May 25, 2026
A LIBRARY FOR SECURITY RESEARCHERS

CWE WEAKNESSES  /  CWE-76

CWE-76

Improper Neutralization of Equivalent Special Elements

Base EXPLOIT LIKELIHOOD: HIGH

What it is

The product correctly neutralizes certain special elements, but it improperly neutralizes equivalent special elements.

The product may have a fixed list of special characters it believes is complete. However, there may be alternate encodings, or representations that also have the same meaning. For example, the product may filter out a leading slash (/) to prevent absolute path names, but does not account for a tilde (~) followed by a user name, which on some *nix systems could be expanded to an absolute pathname. Alternately, the product might filter a dangerous "-e" command-line switch when calling an external program, but it might not account for "--exec" or other switches that have the same semantics.

Impact

OtherOther

Mitigations

  • [Requirements] Programming languages and supporting technologies might be chosen which are not subject to these issues.
  • [Implementation] Utilize an appropriate mix of allowlist and denylist parsing to filter equivalent special element syntax from all input.

Related weaknesses

Test & detect

Browse all common weaknesses, check related exploited CVEs, or map to ATT&CK techniques.

Source: MITRE CWE. View on cwe.mitre.org →

Scroll to Top