Chi tiết CWE-560

The product calls umask() with an incorrect argument that is specified as if it is an argument to chmod().

Các cách xuất hiện

Implementation

Nền tảng áp dụng

Ngôn ngữ

Tên: C (Undetermined)

Hậu quả phổ biến

Các biện pháp giảm thiểu tiềm năng

Phases : Implementation
Use umask() with the correct argument.

Phương pháp phát hiện

Automated Static Analysis

If you suspect misuse of umask(), you can use grep to spot call instances of umask().

Ghi chú ánh xạ lỗ hổng

Lý do : This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Bình luận : Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

Ghi chú

Some umask() manual pages begin with the false statement: "umask sets the umask to mask & 0777" Although this behavior would better align with the usage of chmod(), where the user provided argument specifies the bits to enable on the specified file, the behavior of umask() is in fact opposite: umask() sets the umask to ~mask & 0777. The documentation goes on to describe the correct usage of umask(): "The umask is used by open() to set initial file permissions on a newly-created file. Specifically, permissions in the umask are turned off from the mode argument to open(2) (so, for example, the common umask default value of 022 results in new files being created with permissions 0666 & ~022 = 0644 = rw-r--r-- in the usual case where the mode is specified as 0666)."

Gửi

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