Graph error after this night update on Debian 12

[mnh]

Hello,

After this night apt autoupdate from zabbix 7.0.19-1+debian12 to 7.0.20-1+debian12, I have an error message on every graphs on my dashboard:

The graph is shown normally below the error message.

The problem persist even if I create a new graph from scratch. Restarted services changed nothing.
Nothing in zabbix_server.log. Nothing special in apt logs. I have this in my apache2 error.log every time in refresh the webpage:

[Wed Oct 29 10:48:22.685948 2025] [php:warn] [pid 310226:tid 310226] [client X.X.X.X:40614] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:22.686443 2025] [php:warn] [pid 310226:tid 310226] [client X.X.X.X:40614] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:22.686505 2025] [php:warn] [pid 310226:tid 310226] [client X.X.X.X:40614] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:22.695595 2025] [php:warn] [pid 310213:tid 310213] [client X.X.X.X:37498] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:22.696068 2025] [php:warn] [pid 310213:tid 310213] [client X.X.X.X:37498] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:22.696224 2025] [php:warn] [pid 310213:tid 310213] [client X.X.X.X:37498] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:22.696305 2025] [php:warn] [pid 310213:tid 310213] [client X.X.X.X:37498] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:23.924229 2025] [php:warn] [pid 310211:tid 310211] [client X.X.X.X:40666] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:23.924854 2025] [php:warn] [pid 310211:tid 310211] [client X.X.X.X:40666] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:23.924967 2025] [php:warn] [pid 310211:tid 310211] [client X.X.X.X:40666] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:23.925064 2025] [php:warn] [pid 310211:tid 310211] [client X.X.X.X:40666] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:23.993326 2025] [php:warn] [pid 310225:tid 310225] [client X.X.X.X:40658] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:23.993873 2025] [php:warn] [pid 310225:tid 310225] [client X.X.X.X:40658] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
  [Wed Oct 29 10:48:23.993948 2025] [php:warn] [pid 310225:tid 310225] [client X.X.X.X:40658] PHP Warning: Undefined array key "key_" in /usr/share/zabbix/include/classes/helpers/CGraphHelper.php on line 302, referer: https://[...].net]/zabbix/zabbix.php?action=dashboard.view&dashboardid=366&from=now-2d&to=now
​

Some system info:

# lsb_release -a
No LSB modules are available.
Distributor ID:    Debian
Description:    Debian GNU/Linux 12 (bookworm)
Release:    12
Codename:    bookworm​

Do you an idea about what append?

[mnh]

Ok, after futher investigation, this is a bug in

/usr/share/zabbix/include/classes/helpers/CGraphHelper.php

Line 302, the if condition miss a

!empty($item['key_'])

in the if(...) before the condition.

Manually fixed, hope it will be included in future update.

[mnh]

Ok, after futher investigation, this is a bug in

/usr/share/zabbix/include/classes/helpers/CGraphHelper.php

Line 302, the if condition miss a

!empty($item['key_'])

in the if(...) before the condition.

Manually fixed, hope it will be included in future update.