CAPEC-492

Regular Expression Exponential Blowup
2014-06-23
00h00 +00:00
Draft
2022-02-22
00h00 +00:00
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Quản lý thông báo

Mô tả CAPEC

An adversary may execute an attack on a program that uses a poor Regular Expression(Regex) implementation by choosing input that results in an extreme situation for the Regex. A typical extreme situation operates at exponential time compared to the input size. This is due to most implementations using a Nondeterministic Finite Automaton(NFA) state machine to be built by the Regex algorithm since NFA allows backtracking and thus more complex regular expressions.

Thông tin CAPEC

Điều kiện tiên quyết

This type of an attack requires the ability to identify hosts running a poorly implemented Regex, and the ability to send crafted input to exploit the regular expression.

Các biện pháp giảm thiểu

Test custom written Regex with fuzzing to determine if the Regex is a poor one. Add timeouts to processes that handle the Regex logic. If an evil Regex is found rewrite it as a good Regex.

Điểm yếu liên quan

CWE-ID Tên điểm yếu

CWE-400

Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource.

CWE-1333

Inefficient Regular Expression Complexity
The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

Tài liệu tham khảo

REF-421

Regular Expression Denial of Service Attacks and Defenses
Bryan Sullivan.
http://msdn.microsoft.com/en-au/magazine/ff646973.aspx

Gửi

Tên Tổ chức Ngày Ngày phát hành
CAPEC Content Team The MITRE Corporation 2014-06-23 +00:00

Sửa đổi

Tên Tổ chức Ngày Bình luận
CAPEC Content Team The MITRE Corporation 2019-04-04 +00:00 Updated Related_Weaknesses
CAPEC Content Team The MITRE Corporation 2019-09-30 +00:00 Updated Related_Attack_Patterns
CAPEC Content Team The MITRE Corporation 2020-12-17 +00:00 Updated Taxonomy_Mappings
CAPEC Content Team The MITRE Corporation 2021-06-24 +00:00 Updated Related_Weaknesses
CAPEC Content Team The MITRE Corporation 2022-02-22 +00:00 Updated Description, Extended_Description