allowDeny

Glob-based allow / deny on the package identifier (not the version). Deny matches always win.

Configuration

- type: allowDeny
  patterns: "Microsoft.*;System.*;Newtonsoft.*;!*.Internal"

The patterns string is a semicolon-separated list. Blank entries are ignored. Each entry is either an allow pattern or, when prefixed with !, a deny pattern. Whitespace around individual patterns is trimmed.

Glob syntax

• * matches zero or more characters.
• ? matches exactly one character.
• All other characters match literally; regex metacharacters in package IDs are matched as-is.
• Matching is case-insensitive, matching NuGet's id case-folding.

Internally each glob is compiled to a Regex with a 50 ms timeout — long enough for any sane id, short enough to block pathological patterns.

Semantics

The rule walks the patterns once per version and applies these rules in order:

1. Deny wins. If any deny pattern matches, the version is rejected immediately. Allow patterns are not consulted.
2. Deny-only configuration. If there are no allow patterns, every non-denied version is allowed.
3. Allow-list mode. If at least one allow pattern is present, the version must match at least one allow pattern; otherwise it is rejected.

Worked examples

patterns: "Microsoft.*;System.*"

Allow list. Only IDs starting with Microsoft. or System. pass.

patterns: "!Internal.*"

Deny only. Everything passes except IDs starting with Internal..

patterns: "Microsoft.*;System.*;!Microsoft.Internal.*"

Allow Microsoft.* and System.*, but reject Microsoft.Internal.*. Deny wins, so Microsoft.Internal.Tools is rejected even though it matches the Microsoft.* allow pattern.

patterns: ""

Empty — the rule allows everything. Equivalent to omitting the rule entirely.

Deny reasons

When an allow-list excludes a version:

{
  "ruleName": "allowDeny",
  "detail": "package does not match any allow pattern"
}

When a deny pattern matches:

{
  "ruleName": "allowDeny",
  "detail": "package matches deny pattern '!Internal.*'"
}

Errors at config time

A pattern of just ! is rejected at startup:

ArgumentException: deny pattern cannot be empty after '!'

Empty / blank patterns are silently dropped, so list trimming is forgiving.

What it does not do

• It matches on the id, not the version string. To gate by SemVer range, layer this rule with a future version-bound rule, or combine with minAgeDays.
• It is not a CVE filter — allowDeny says nothing about safety, only about whether the id is on your list.