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Dữ liệu MITRE CWE chính thức

TOCTTOU — The TOCTTOU acronym expands to "Time Of Check To Time Of Use".
TOCCTOU — The TOCCTOU acronym is most likely a typo of TOCTTOU, but it has been used in some influential documents, so the typo is repeated fairly frequently.

Hiện thực hóa: This weakness can be security-relevant when an attacker can influence the state of the resource between check and use. This can happen with shared resources such as files, memory, or even variables in multithreaded programs.

Dữ liệu MITRE CWE chính thức

Tác động	Phạm vi	Diễn giải
Thay đổi logic thực thi, Trạng thái ngoài dự kiến	Tính toàn vẹn, Khác	The attacker can gain access to otherwise unauthorized resources.
Thay đổi dữ liệu ứng dụng, Thay đổi tệp hoặc thư mục, Thay đổi bộ nhớ, Khác	Tính toàn vẹn, Khác	Race conditions such as this kind may be employed to gain read or write access to resources which are not normally readable or writable by the user in question.
Khác	Tính toàn vẹn, Khác	The resource in question, or other resources (through the corrupted one), may be changed in undesirable ways by a malicious user.
Che giấu hoạt động	Chống chối bỏ	If a file or other resource is written in this method, as opposed to in a valid way, logging of the activity may not occur.
Khác	Chống chối bỏ, Khác	In some cases it may be possible to delete files a malicious user might not otherwise have access to, such as log files.
Trạng thái ngoài dự kiến	Khác	The product may perform invalid actions when the resource is in an unexpected state.

Dữ liệu MITRE CWE chính thức

Hiện thực hóaThe most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
Hiện thực hóaWhen the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
Kiến trúc và thiết kếLimit the interleaving of operations on files from multiple processes.
Hiện thực hóa, Kiến trúc và thiết kếIf you cannot perform operations atomically and you must share access to the resource between multiple processes or threads, then try to limit the amount of time (CPU cycles) between the check and use of the resource. This will not fix the problem, but it could make it more difficult for an attack to succeed.
Hiện thực hóaRecheck the resource after the use call to verify that the action was taken appropriately.
Kiến trúc và thiết kếEnsure that some environmental locking mechanism can be used to protect resources effectively.
Hiện thực hóaEnsure that locking occurs before the check, as opposed to afterwards, such that the resource, as checked, is the same as it is when in use.

Dữ liệu MITRE CWE chính thức

Phương pháp	Cách làm	Hiệu quả
Phân tích tĩnh tự động	Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)	Cao

Dữ liệu MITRE CWE chính thức

Dưới đây là các lỗ hổng tiêu biểu liên quan đến CWE-367, dựa theo mức độ ưu tiên

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