Picomatch: Method Injection in POSIX Character Classes causes incorrect Glob Matching

Picomatch is a glob matcher written JavaScript. Versions prior to 4.0.4, 3.0.2, and 2.3.2 are vulnerable to a method injection vulnerability affecting the `POSIX_REGEX_SOURCE` object. Because the object inherits from `Object.prototype`, specially crafted POSIX bracket expressions (e.g., `[[:constructor:]]`) can reference inherited method names. These methods are implicitly converted to strings and injected into the generated regular expression. This leads to incorrect glob matching behavior (integrity impact), where patterns may match unintended filenames. The issue does not enable remote code execution, but it can cause security-relevant logic errors in applications that rely on glob matching for filtering, validation, or access control. All users of affected `picomatch` versions that process untrusted or user-controlled glob patterns are potentially impacted. This issue is fixed in picomatch 4.0.4, 3.0.2 and 2.3.2. Users should upgrade to one of these versions or later, depending on their supported release line. If upgrading is not immediately possible, avoid passing untrusted glob patterns to picomatch. Possible mitigations include sanitizing or rejecting untrusted glob patterns, especially those containing POSIX character classes like `[[:...:]]`; avoiding the use of POSIX bracket expressions if user input is involved; and manually patching the library by modifying `POSIX_REGEX_SOURCE` to use a null prototype.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE-1321

Picomatch 安全漏洞

Picomatch是micromatch开源的一个JavaScript编写的快速且准确的Glob模式匹配库。 Picomatch 4.0.4之前版本、3.0.2之前版本和2.3.2之前版本存在安全漏洞，该漏洞源于POSIX_REGEX_SOURCE对象存在方法注入，可能导致不正确的全局匹配行为。

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