ModSecurity を使用して AEM サイトを DoS 攻撃から保護する方法

# Replace the X.Y.Z with relevent version numbers.
$ wget https://github.com/coreruleset/coreruleset/archive/refs/tags/vX.Y.Z.tar.gz

# For version v3.3.5 when this tutorial is published
$ wget https://github.com/coreruleset/coreruleset/archive/refs/tags/v3.3.5.tar.gz

# Extract the downloaded file
$ tar -xvzf coreruleset-3.3.5.tar.gz

# Go inside the newly created rules directory within the dispathcher module
$ cd dispatcher/src/conf.d/modsec/crs/rules

# Rename all '.conf' extension files to '.conf.disabled'
$ for i in *.conf; do mv -- "$i" "$i.disabled"; done

# The Denial of Service (DoS) protection against clients making requests too quickly.
# When a client is making more than 25 requests (excluding static files) within
# 60 seconds, this is considered a 'burst'. After two bursts, the client is
# blocked for 600 seconds.
SecAction \
    "id:900700,\
    phase:1,\
    nolog,\
    pass,\
    t:none,\
    setvar:'tx.dos_burst_time_slice=60',\
    setvar:'tx.dos_counter_threshold=25',\
    setvar:'tx.dos_block_timeout=600'"

########################################################
# AEM as a Cloud Service exclusions                    #
########################################################
# Ignoring AEM-CS Specific internal and reserved paths

SecRule REQUEST_URI "@beginsWith /systemready" \
    "id:1010,\
    phase:1,\
    pass,\
    nolog,\
    ctl:ruleEngine=Off"

SecRule REQUEST_URI "@beginsWith /system/probes" \
    "id:1011,\
    phase:1,\
    pass,\
    nolog,\
    ctl:ruleEngine=Off"

SecRule REQUEST_URI "@beginsWith /gitinit-status" \
    "id:1012,\
    phase:1,\
    pass,\
    nolog,\
    ctl:ruleEngine=Off"

########################################################
# ADD YOUR SITE related exclusions                     #
########################################################
...

# Include the baseline crs setup
Include conf.d/modsec/crs/crs-setup.conf

# Include your customizations to crs setup if exist
IncludeOptional conf.d/modsec/crs/crs-setup.custom.conf

# Select all available CRS rules:
#Include conf.d/modsec/crs/rules/*.conf

# Or alternatively list only specific ones you want to enable e.g.
Include conf.d/modsec/crs/rules/REQUEST-900-EXCLUSION-RULES-BEFORE-CRS.conf
Include conf.d/modsec/crs/rules/REQUEST-901-INITIALIZATION.conf
Include conf.d/modsec/crs/rules/REQUEST-905-COMMON-EXCEPTIONS.conf
Include conf.d/modsec/crs/rules/REQUEST-910-IP-REPUTATION.conf
Include conf.d/modsec/crs/rules/REQUEST-912-DOS-PROTECTION.conf
Include conf.d/modsec/crs/rules/REQUEST-949-BLOCKING-EVALUATION.conf

# Start initially with engine off, then switch to detection and observe, and when sure enable engine actions
#SecRuleEngine Off
#SecRuleEngine DetectionOnly
SecRuleEngine On

# Remember to use relative path for logs:
SecDebugLog logs/httpd_mod_security_debug.log

# Start with low debug level
SecDebugLogLevel 0
#SecDebugLogLevel 1

# Start without auditing
SecAuditEngine Off
#SecAuditEngine RelevantOnly
#SecAuditEngine On

# Tune audit accordingly:
SecAuditLogRelevantStatus "^(?:5|4(?!04))"
SecAuditLogParts ABIJDEFHZ
SecAuditLogType Serial

# Remember to use relative path for logs:
SecAuditLog logs/httpd_mod_security_audit.log

# You might still use /tmp for temporary/work files:
SecTmpDir /tmp
SecDataDir /tmp

# Enable the ModSecurity and OWASP CRS
<IfModule mod_security2.c>
    Include conf.d/modsec/modsecurity.conf
</IfModule>

...

<VirtualHost *:80>
    ServerName    "publish"
    ...
</VirtualHost>

Tue Aug 15 15:19:40.229262 2023 [security2:error] [pid 308:tid 140200050567992] [cm-p46652-e1167810-aem-publish-85df5d9954-bzvbs] [client 192.150.10.209] ModSecurity: Warning. Operator GE matched 2 at IP:dos_burst_counter. [file "/etc/httpd/conf.d/modsec/crs/rules/REQUEST-912-DOS-PROTECTION.conf"] [line "265"] [id "912170"] [msg "Potential Denial of Service (DoS) Attack from 192.150.10.209 - # of Request Bursts: 2"] [ver "OWASP_CRS/3.3.5"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "paranoia-level/1"] [tag "attack-dos"] [tag "OWASP_CRS"] [tag "capec/1000/210/227/469"] [hostname "publish-p46652-e1167810.adobeaemcloud.com"] [uri "/content/wknd/us/en/adventures.html"] [unique_id "ZNuXi9ft_9sa85dovgTN5gAAANI"]

...

Tue Aug 15 15:19:40.515237 2023 [security2:error] [pid 309:tid 140200051428152] [cm-p46652-e1167810-aem-publish-85df5d9954-bzvbs] [client 192.150.10.209] ModSecurity: Access denied with connection close (phase 1). Operator EQ matched 0 at IP. [file "/etc/httpd/conf.d/modsec/crs/rules/REQUEST-912-DOS-PROTECTION.conf"] [line "120"] [id "912120"] [msg "Denial of Service (DoS) attack identified from 192.150.10.209 (1 hits since last alert)"] [ver "OWASP_CRS/3.3.5"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "paranoia-level/1"] [tag "attack-dos"] [tag "OWASP_CRS"] [tag "capec/1000/210/227/469"] [hostname "publish-p46652-e1167810.adobeaemcloud.com"] [uri "/us/en.html"] [unique_id "ZNuXjAN7ZtmIYHGpDEkmmwAAAQw"]