Category: Database Security

Database Security

Aug 17

Oracle Database causing Linux auditd logs to grow fast

Those days I was having some issues on some of my Oracle Linux 6 servers (VMs in OCI), with some Oracle Databases running still in project phase. I could notice /var/log/audit folder size growing abnormally (around ~80MBs day) [root@ocasxxxt00dbre1 audit]# ls -ltrh | tail -n 30 -r--------. 1 root root 6.1M Aug 15 10:24 audit.log.29 …

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Aug 09

Dissecting 180717 BP, PSU, RU and RUR

Since Oct-2017 I am quarterly writing a post dissecting the changes implemented by Oracle CPUs so we can understand better the modifications implemented by Oracle in our Databases. This is the first one to include change on 18c version. So what oracle internal objects were changed in 180717? VERSION PATCH OWNER TYPE TOTAL ---------- --------------- …

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Jun 11

Protecting Oracle Database Binaries against malicious changes

Introduction In the live sessions where I talk about Oracle Database security and vulnerabilities, I do always mention rootkits or malwares that can attack a database from either inside (via SQL injection, PL/SQL poisoning, Java leaks, etc) or externally (by changing oracle user files, such as binaries / libs / crontab / etc). To explore …

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May 29

How to bypass requirement of WITH GRANT OPTION on views accessing third-party tables

A long time back, Oracle introduced limitations on VIEWS to avoid that some user with access to a given object in the database to pass on its contents to another user, by encapsulating it on views. As it's always better to show examples than writing theory, let's say we have 3 users on the database …

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May 10

Dissecting 180417 BP, PSU, RU and RUR

Since Oct-2017 I am quarterly writing a post dissecting the changes implemented by Oracle CPUs so we can understand better the modifications implemented by Oracle in our Databases. So what oracle internal objects were changed in 180417? VERSION PATCH OWNER TYPE TOTAL -------------------- ---------- ------------------------------ ------------------------------ ---------- 12.1.0.2 BP SYS PACKAGE 1 12.1.0.2 BP SYS …

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