Hello. What I can read from logs is that you have 3 errors: A) Warning about User-Agent required..normally when you use a browser you send your User-Agent to the web server:"REQUEST_HEADERS:User-Agent" required. I'm not sure if that computer is hidding it in someway and that's the reason of that warning
B)Notice concerning about protocol enforcement: Request Missing an Accept Header: This is similar to ACK sent by servers when a protocol receives a client SYN.In http/s you can force for a accept header and modsecurity is checking it. C)ModSecurity is detecting several sql injection bypasses: REQUEST_COOKIES:OutlookSession. [file "/usr/share/owasp-modsecurity-crs/rules/REQUEST-942-APPLICATION-ATTACK-SQLI.conf"] [line "705"] [id "942260"] [rev "2"] [msg "Detects basic SQL authentication bypass attempts 2/3"] The first 2 warnings are not very important, you could whitelist ip for the 2 first rules: 1)REQUEST-920-PROTOCOL-ENFORCEMENT.conf"] [line "1251"] [id "920300"] 2)[msg "Request Missing an Accept Header"] [severity "NOTICE"] [ver "OWASP_CRS/3.0.0"] [maturity "9"] [accuracy "8"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "attack-protocol"] [tag "OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_ACCEPT"] I'm not completely sure that computer is clean of malware because of third error: REQUEST_COOKIES:OutlookSession. [file "/usr/share/owasp-modsecurity-crs/rules/REQUEST-942-APPLICATION-ATTACK-SQLI.conf"] [line "705"] [id "942260"] [rev "2"] [msg "Detects basic SQL authentication bypass attempts 2/3"] It seems that computer is trying to access OWA (Outlook web access) and it seems is masking USER-AGENT and ignoring ACCEPT header that many bots like Spasm sources ignore many protocol rules. You could whitelist that ip but I would perform malware analysis, memory dump and forensic stuff on that computer. I recently had to format my computer because it was doing connections and I wasn't able to detect the source with TCP view (Mark Russinovich great windows tool), netstat and process explorer. Regards El mar., 15 de noviembre de 2016 17:59, kamil kapturkiewicz <hor...@wp.pl> escribió: > Hi, > I have had this issue with previous 2.2.9 version, but I am not really > sure is related to mod_security it self or to CRS. The problem is with some > Windows machines, below is the example from one of our corporate user, who > is working on Windows 7 machine. I am pretty sure machine is not infected > by malware or something, and this problem occures on FF, Chrome, Opera and > IE. But in combination with fail2ban, this cut him off from web server > every time he is trying to access company website. Do > you guys have any idea what is causing this? > > [Tue Nov 15 16:26:41.962933 2016] [:error] [pid 31434] [client > 213.81.82.201] ModSecurity: Warning. Match of "pm > AppleWebKit Android" against "REQUEST_HEADERS:User-Agent" required. [file > "/usr/share/owasp-modsecurity-crs/rules/REQUEST-920-PROTOCOL-ENFORCEMENT.conf"] > [line "1251"] [id "920300"] [rev "3"] [msg "Request Missing an Accept > Header"] [severity "NOTICE"] [ver "OWASP_CRS/3.0.0"] [maturity "9"] > [accuracy "8"] [tag "application-multi"] [tag "language-multi"] [tag > "platform-multi"] [tag "attack-protocol"] [tag > "OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_ACCEPT"] [tag > "WASCTC/WASC-21"] [tag > "OWASP_TOP_10/A7"] [tag "PCI/6.5.10"] [tag "paranoia-level/2"] [hostname " > domain.com"] [uri "/autodiscover/autodiscover.xml"] [unique_id > "WCs3QX8AAQEAAHrKJTMAAAAF"] > [Tue Nov 15 16:26:41.963976 2016] [:error] [pid 31434] [client > 213.81.82.201] ModSecurity: Access denied with code 403 (phase 2). Pattern > match > "(?i:(?:union\\\\s*?(?:all|distinct|[(!@]*?)?\\\\s*?[([]*?\\\\s*?select\\\\s+)|(?:\\\\w+\\\\s+like\\\\s+[\\"'`])|(?:like\\\\s*?[\\"'`]\\\\%)|(?:[\\"'`]\\\\s*?like\\\\W*?[\\"'`\\\\d])|(?:[\\"'`]\\\\s*?(?:n?and|x?x?or|div|like|between|and|not|\\\\|\\\\||\\\\&\\\\&)\\\\s+[\\\\s\\\\w]+=\\\\s*?\\\\w+\\\\s*?h > ..." at REQUEST_COOKIES:OutlookSession. [file > "/usr/share/owasp-modsecurity-crs/rules/REQUEST-942-APPLICATION-ATTACK-SQLI.conf"] > [line "705"] [id "942260"] [rev "2"] [msg "Detects basic SQL authentication > bypass attempts 2/3"] [data "Matched Data: \\x22{BB1B2590-E found within > REQUEST_COOKIES:OutlookSession: > \\x22{BB1B2590-EEE9-451E-9ABD-B75491F282EE}\\x22"] [severity "CRITICAL"] > [ver "OWASP_CRS/3.0.0"] [maturity "9"] [accuracy "8"] [tag > "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag > "attack-sqli"] [tag > "OWASP_CRS/WEB_ATTACK/SQL_INJECTION"] [tag "WASCTC/WASC-19"] [tag > "OWASP_TOP_10/A1"] [tag "OWASP_AppSensor/CIE1"] [tag "PCI/6.5.2"] [tag > "paranoia-level/2"] [hostname "domain.com"] [uri > "/autodiscover/autodiscover.xml"] [unique_id "WCs3QX8AAQEAAHrKJTMAAAAF"] > [Tue Nov 15 16:26:44.390517 2016] [:error] [pid 31254] [client > 213.81.82.201] ModSecurity: Warning. Match of "pm AppleWebKit Android" > against "REQUEST_HEADERS:User-Agent" required. [file > "/usr/share/owasp-modsecurity-crs/rules/REQUEST-920-PROTOCOL-ENFORCEMENT.conf"] > [line "1251"] [id "920300"] [rev "3"] [msg "Request Missing an Accept > Header"] [severity "NOTICE"] [ver "OWASP_CRS/3.0.0"] [maturity "9"] > [accuracy "8"] [tag "application-multi"] [tag "language-multi"] [tag > "platform-multi"] [tag > "attack-protocol"] [tag > "OWASP_CRS/PROTOCOL_VIOLATION/MISSING_HEADER_ACCEPT"] [tag > "WASCTC/WASC-21"] [tag "OWASP_TOP_10/A7"] [tag "PCI/6.5.10"] [tag > "paranoia-level/2"] [hostname "domain.com"] [uri > "/autodiscover/autodiscover.xml"] [unique_id "WCs3RH8AAQEAAHoWjIUAAAAD"] > [Tue Nov 15 16:26:44.391535 2016] [:error] [pid 31254] [client > 213.81.82.201] ModSecurity: Access denied with code 403 (phase 2). Pattern > match > "(?i:(?:union\\\\s*?(?:all|distinct|[(!@]*?)?\\\\s*?[([]*?\\\\s*?select\\\\s+)|(?:\\\\w+\\\\s+like\\\\s+[\\"'`])|(?:like\\\\s*?[\\"'`]\\\\%)|(?:[\\"'`]\\\\s*?like\\\\W*?[\\"'`\\\\d])|(?:[\\"'`]\\\\s*?(?:n?and|x?x?or|div|like|between|and|not|\\\\|\\\\||\\\\&\\\\&)\\\\s+[\\\\s\\\\w]+=\\\\s*?\\\\w+\\\\s*?h > ..." at REQUEST_COOKIES:OutlookSession. [file > "/usr/share/owasp-modsecurity-crs/rules/REQUEST-942-APPLICATION-ATTACK-SQLI.conf"] > [line "705"] [id "942260"] [rev "2"] [msg "Detects basic SQL authentication > bypass attempts 2/3"] [data "Matched Data: \\x22{BB1B2590-E found within > REQUEST_COOKIES:OutlookSession: > \\x22{BB1B2590-EEE9-451E-9ABD-B75491F282EE}\\x22"] [severity "CRITICAL"] > [ver "OWASP_CRS/3.0.0"] [maturity "9"] [accuracy "8"] [tag > "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag > "attack-sqli"] [tag > "OWASP_CRS/WEB_ATTACK/SQL_INJECTION"] [tag "WASCTC/WASC-19"] [tag > "OWASP_TOP_10/A1"] [tag "OWASP_AppSensor/CIE1"] [tag "PCI/6.5.2"] [tag > "paranoia-level/2"] [hostname "domain.com"] [uri > "/autodiscover/autodiscover.xml"] [unique_id "WCs3RH8AAQEAAHoWjIUAAAAD"] > > > > > _______________________________________________ > Owasp-modsecurity-core-rule-set mailing list > Owasp-modsecurity-core-rule-set@lists.owasp.org > https://lists.owasp.org/mailman/listinfo/owasp-modsecurity-core-rule-set >
_______________________________________________ Owasp-modsecurity-core-rule-set mailing list Owasp-modsecurity-core-rule-set@lists.owasp.org https://lists.owasp.org/mailman/listinfo/owasp-modsecurity-core-rule-set