After several hours of investigation I’ve found that my site has heen attacked with 160k+ attempts to bruteforce my administrative account, so this caused my virtual host to exceed the CPU time limits. This problem was instantly solved only after I added IP of the attacker to deny list in the.htaccess file.
My hoster BTW didn’t found the cause of this problem, but did something with limits allowing me to at least access the site during my investigation.
So, problem solved, the cause is described above.
Hi!
The exactly same problem since 19 July with the WordPress 4.2.3.
Site: modularsynth.ru
Hoster: hostyes.ru
PHP version: now switched to 5.3.29 (THe only available 5.2 branch is 5.2.17 and WP requires 5.2.24)