界: Input Validation and Representation

輸入驗證和表示法問題是由中繼字元、替代編碼和數值表示法引起的。信任輸入會導致安全問題。問題包括：「Buffer Overflows」、「Cross-Site Scripting」攻擊、「SQL Injection」及其他許多問題。

Memcached Injection

C#/VB.NET/ASP.NET
Python

Abstract

使用不可信賴之來源中的輸入叫用 Memcached 作業可能會讓攻擊者在 Memcached 快取中引入新的索引鍵/值組。

Explanation

在以下情況下會發生 Memcached injection 錯誤：

1. 資料從一個不可信賴的來源進入程式。

2. 資料用來動態建構 Memcached 索引鍵或值。

範例 1：以下程式碼會動態建構 Memcached 索引鍵。


    ...
            TextClient tc = (TextClient)Client.GetInstance("127.0.0.1", 11211, MemcachedFlags.TextProtocol);
            tc.Open();
            string id = txtID.Text;
            var result = get_page_from_somewhere();
            var response = Http_Response(result);
            tc.Set("req-" + id, response, TimeSpan.FromSeconds(1000));
            tc.Close();
            tc = null;
    ...

此程式碼欲執行的作業如下所示：


    set req-1233 0 1000 n
    <serialized_response_instance>

其中 n 是回應的長度。

然而，由於是透過串聯常數索引鍵字首和使用者輸入字串來動態建構該作業，因此，攻擊者可能傳送 ignore 0 0 1\r\n1\r\nset injected 0 3600 10\r\n0123456789\r\nset req- 字串，然後作業會變成如下所示：


    set req-ignore 0 0 1
    1
    set injected 0 3600 10
    0123456789
    set req-1233 0 0 n
    <serialized_response_instance>

上述金鑰將在 injected=0123456789 快取中成功新增索引鍵/值組，所以攻擊者將能夠破壞快取。

References

[1] Novikov The New Page Of Injections Book: Memcached Injections

[2] Standards Mapping - Common Weakness Enumeration CWE ID 20

[3] Standards Mapping - Common Weakness Enumeration Top 25 2019 [3] CWE ID 020

[4] Standards Mapping - Common Weakness Enumeration Top 25 2020 [3] CWE ID 020

[5] Standards Mapping - Common Weakness Enumeration Top 25 2021 [4] CWE ID 020

[6] Standards Mapping - Common Weakness Enumeration Top 25 2022 [4] CWE ID 020

[7] Standards Mapping - Common Weakness Enumeration Top 25 2023 [6] CWE ID 020

[8] Standards Mapping - Common Weakness Enumeration Top 25 2024 [12] CWE ID 020

[9] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-002754

[10] Standards Mapping - FIPS200 SI

[11] Standards Mapping - General Data Protection Regulation (GDPR) Indirect Access to Sensitive Data

[12] Standards Mapping - NIST Special Publication 800-53 Revision 4 SI-10 Information Input Validation (P1)

[13] Standards Mapping - NIST Special Publication 800-53 Revision 5 SI-10 Information Input Validation

[14] Standards Mapping - OWASP Application Security Verification Standard 4.0 5.1.3 Input Validation Requirements (L1 L2 L3), 5.1.4 Input Validation Requirements (L1 L2 L3)

[15] Standards Mapping - OWASP Mobile 2024 M4 Insufficient Input/Output Validation

[16] Standards Mapping - OWASP Top 10 2004 A6 Injection Flaws

[17] Standards Mapping - OWASP Top 10 2007 A2 Injection Flaws

[18] Standards Mapping - OWASP Top 10 2010 A1 Injection

[19] Standards Mapping - OWASP Top 10 2013 A1 Injection

[20] Standards Mapping - OWASP Top 10 2017 A1 Injection

[21] Standards Mapping - OWASP Top 10 2021 A03 Injection

[22] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 Requirement 6.5.6

[23] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 Requirement 6.3.1.1, Requirement 6.5.2

[24] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 Requirement 6.5.1

[25] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 6.5.1

[26] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.1

[27] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.1

[28] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.1

[29] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0 Requirement 6.2.4

[30] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0.1 Requirement 6.2.4

[31] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 4.2 - Critical Asset Protection

[32] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 4.2 - Critical Asset Protection, Control Objective B.3.1 - Terminal Software Attack Mitigation, Control Objective B.3.1.1 - Terminal Software Attack Mitigation

[33] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 4.2 - Critical Asset Protection, Control Objective B.3.1 - Terminal Software Attack Mitigation, Control Objective B.3.1.1 - Terminal Software Attack Mitigation, Control Objective C.3.2 - Web Software Attack Mitigation

[34] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3510 CAT I

[35] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3510 CAT I

[36] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3510 CAT I

[37] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3510 CAT I

[38] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3510 CAT I

[39] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3510 CAT I

[40] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3510 CAT I

[41] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002560 CAT I

[42] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002560 CAT I

[43] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002560 CAT I

[44] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002560 CAT I

[45] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002560 CAT I

[46] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002560 CAT I

[47] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002560 CAT I

[48] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002560 CAT I

[49] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002560 CAT I

[50] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002560 CAT I

[51] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002560 CAT I

[52] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002560 CAT I

[53] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002560 CAT I

[54] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002530 CAT II, APSC-DV-002560 CAT I

[55] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002530 CAT II, APSC-DV-002560 CAT I

[56] Standards Mapping - Web Application Security Consortium Version 2.00 Improper Input Handling (WASC-20)

desc.dataflow.dotnet.memcached_injection

Abstract

使用不可信賴之來源中的輸入呼叫 Memcached 作業可能會讓攻擊者在 Memcached 快取中引入新的索引鍵/值組。

Explanation


...
def store(request):
    id = request.GET['id']
    result = get_page_from_somewhere()
    response = HttpResponse(result)
    cache_time = 1800
    cache.set("req-" % id, response, cache_time)
    return response
...

此程式碼欲執行的作業如下所示：


set req-1233 0 0 n
<serialized_response_instance>

然而，由於是透過串聯常數索引鍵字首和使用者輸入字串來動態建構該作業，因此，攻擊者可能傳送 ignore 0 0 1\r\n1\r\nset injected 0 3600 10\r\n0123456789\r\nset req- 字串，然後作業會變成如下所示：


set req-ignore 0 0 1
1
set injected 0 3600 10
0123456789
set req-1233 0 0 n
<serialized_response_instance>

上述索引鍵將在 injected=0123456789 快取中成功新增索引鍵/值組。視裝載而定，攻擊者將能夠透過插入由 Pickle 序列化的裝載 (在還原序列化之後會執行任意程式碼)，破壞快取或執行任意程式碼。