I decided to investigate this further. This is repeatable in both Safari (Version 18.0 (19619.1.26.111.10, 19619)) and in Google Chrome (Version 128.0.6613.138 (Official Build) (arm64)). MacBook Pro, Apple M1 Pro, MacOS 14.6.1 (23G93).

I had two registration requests. Registrations are moderatored, requiring admin approval. So, I tested one in Safari and one in Chrome. In both cases, after approving the registration, I tried to return to the dashboard and got an error. So, I decided to repeat the experiment and capture the admin cookie values.

This is the results:
Admin cookie before approval;
Quote
a:7:{s:11:"newmembers1";s:1:"4";s:11:"newmembers7";s:1:"9";s:12:"newmembers31";s:2:"30";s:9:"alogcount";s:5:"40635";s:9:"rlogcount";s:4:"1292";s:4:"modq";s:1:"0";s:9:"timestamp";i:1726869011;}

Dashboard after approval:
Quote
This page isn’t workingwww.stovebolt.com is currently unable to handle this request.
HTTP ERROR 500

Admin cookie after approval:
Quote
s:192:"a:7:{s:11:"newmembers1";s:1:"4";s:11:"newmembers7";s:1:"9";s:12:"newmembers31";s:2:"30";s:9:"alogcount";s:5:"40789";s:9:"rlogcount";s:4:"1352";s:4:"modq";s:1:"2";s:9:"timestamp";i:1726901754;}";

Notice that characters were prepended (s:192:") to the existing cookie. The only other thing that has changed is what appears to be a unix timestamp at the end of the cookie.

I expired cookies, logged back in, loaded the dashboard successfully. Then I checked the admin cookie again.
Quote
a:7:{s:11:"newmembers1";s:1:"3";s:11:"newmembers7";s:2:"10";s:12:"newmembers31";s:2:"31";s:9:"alogcount";s:5:"40790";s:9:"rlogcount";s:4:"1352";s:4:"modq";s:1:"1";s:9:"timestamp";i:1726901905;}

I approved the second registration, then returned to the dashboard again.
Quote
This page isn’t workingwww.stovebolt.com is currently unable to handle this request.
HTTP ERROR 500

I checked the cookie again:
Quote
s:193:"a:7:{s:11:"newmembers1";s:1:"3";s:11:"newmembers7";s:2:"10";s:12:"newmembers31";s:2:"31";s:9:"alogcount";s:5:"40790";s:9:"rlogcount";s:4:"1352";s:4:"modq";s:1:"1";s:9:"timestamp";i:1726901905;}";

Notice that again, characters have been prepended (s:193:") to the cookie but they appear to have been incremented by one.


The Stovebolt Geek
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