@nronline Please set temporally $error_reporting='maximum' and $debug='1' in configuration.php file and post a screenshot

@wojsmol reading "Migration" thinking on you.

ah, faster.

@franz-wohlkoenig Only screenshot here if further diagnostics will be needed then I will redirect to forums.

Hi guys, screenshot attached as requested

@nronline I don't see any screenshot.

Screenshot's on the original issue comment.

Issue presented itself after two weeks from updating to 3.8.10. Not sure why. No changes to the system have taken place during this time at all.

Based on that stack trace alone, either there is a majorly broken reference somewhere in the Registry API or something is messing with the user object reference in the Session API. The only way that error could even feasibly raise itself is if the reference inside Joomla\Registry\Registry::set() is somehow pointing to a Joomla\CMS\Menu\AbstractMenu instance, and again that to me points to something messing with the data in the Session API or references are beyond busted in the Registry API.

That's strange though as the development environment is a mirror of live and is functioning fine. Also if there is an issue with the zip i downloaded then perhaps updating to Joomla 3.8.11 may resolve.

Failing that I could disable plugins/components to see if i can identify 3rd party code thats interfering, or just rollback.

Registry file in question here

<?php
/**
 * Part of the Joomla Framework Registry Package
 *
 * @copyright  Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license    GNU General Public License version 2 or later; see LICENSE
 */

namespace Joomla\Registry;

use Joomla\Utilities\ArrayHelper;

/**
 * Registry class
 *
 * @since  1.0
 */
class Registry implements \JsonSerializable, \ArrayAccess, \IteratorAggregate, \Countable
{
	/**
	 * Registry Object
	 *
	 * @var    \stdClass
	 * @since  1.0
	 */
	protected $data;

	/**
	 * Flag if the Registry data object has been initialized
	 *
	 * @var    boolean
	 * @since  1.5.2
	 */
	protected $initialized = false;

	/**
	 * Registry instances container.
	 *
	 * @var    Registry[]
	 * @since  1.0
	 * @deprecated  2.0  Object caching will no longer be supported
	 */
	protected static $instances = array();

	/**
	 * Path separator
	 *
	 * @var    string
	 * @since  1.4.0
	 */
	public $separator = '.';

	/**
	 * Constructor
	 *
	 * @param   mixed  $data  The data to bind to the new Registry object.
	 *
	 * @since   1.0
	 */
	public function __construct($data = null)
	{
		// Instantiate the internal data object.
		$this->data = new \stdClass;

		// Optionally load supplied data.
		if ($data instanceof Registry)
		{
			$this->merge($data);
		}
		elseif (is_array($data) || is_object($data))
		{
			$this->bindData($this->data, $data);
		}
		elseif (!empty($data) && is_string($data))
		{
			$this->loadString($data);
		}
	}

	/**
	 * Magic function to clone the registry object.
	 *
	 * @return  void
	 *
	 * @since   1.0
	 */
	public function __clone()
	{
		$this->data = unserialize(serialize($this->data));
	}

	/**
	 * Magic function to render this object as a string using default args of toString method.
	 *
	 * @return  string
	 *
	 * @since   1.0
	 */
	public function __toString()
	{
		return $this->toString();
	}

	/**
	 * Count elements of the data object
	 *
	 * @return  integer  The custom count as an integer.
	 *
	 * @link    https://secure.php.net/manual/en/countable.count.php
	 * @since   1.3.0
	 */
	public function count()
	{
		return count(get_object_vars($this->data));
	}

	/**
	 * Implementation for the JsonSerializable interface.
	 * Allows us to pass Registry objects to json_encode.
	 *
	 * @return  object
	 *
	 * @since   1.0
	 * @note    The interface is only present in PHP 5.4 and up.
	 */
	public function jsonSerialize()
	{
		return $this->data;
	}

	/**
	 * Sets a default value if not already assigned.
	 *
	 * @param   string  $key      The name of the parameter.
	 * @param   mixed   $default  An optional value for the parameter.
	 *
	 * @return  mixed  The value set, or the default if the value was not previously set (or null).
	 *
	 * @since   1.0
	 */
	public function def($key, $default = '')
	{
		$value = $this->get($key, $default);
		$this->set($key, $value);

		return $value;
	}

	/**
	 * Check if a registry path exists.
	 *
	 * @param   string  $path  Registry path (e.g. joomla.content.showauthor)
	 *
	 * @return  boolean
	 *
	 * @since   1.0
	 */
	public function exists($path)
	{
		// Return default value if path is empty
		if (empty($path))
		{
			return false;
		}

		// Explode the registry path into an array
		$nodes = explode($this->separator, $path);

		// Initialize the current node to be the registry root.
		$node  = $this->data;
		$found = false;

		// Traverse the registry to find the correct node for the result.
		foreach ($nodes as $n)
		{
			if (is_array($node) && isset($node[$n]))
			{
				$node  = $node[$n];
				$found = true;
				continue;
			}

			if (!isset($node->$n))
			{
				return false;
			}

			$node  = $node->$n;
			$found = true;
		}

		return $found;
	}

	/**
	 * Get a registry value.
	 *
	 * @param   string  $path     Registry path (e.g. joomla.content.showauthor)
	 * @param   mixed   $default  Optional default value, returned if the internal value is null.
	 *
	 * @return  mixed  Value of entry or null
	 *
	 * @since   1.0
	 */
	public function get($path, $default = null)
	{
		// Return default value if path is empty
		if (empty($path))
		{
			return $default;
		}

		if (!strpos($path, $this->separator))
		{
			return (isset($this->data->$path) && $this->data->$path !== null && $this->data->$path !== '') ? $this->data->$path : $default;
		}

		// Explode the registry path into an array
		$nodes = explode($this->separator, trim($path));

		// Initialize the current node to be the registry root.
		$node  = $this->data;
		$found = false;

		// Traverse the registry to find the correct node for the result.
		foreach ($nodes as $n)
		{
			if (is_array($node) && isset($node[$n]))
			{
				$node  = $node[$n];
				$found = true;

				continue;
			}

			if (!isset($node->$n))
			{
				return $default;
			}

			$node  = $node->$n;
			$found = true;
		}

		if (!$found || $node === null || $node === '')
		{
			return $default;
		}

		return $node;
	}

	/**
	 * Returns a reference to a global Registry object, only creating it
	 * if it doesn't already exist.
	 *
	 * This method must be invoked as:
	 * <pre>$registry = Registry::getInstance($id);</pre>
	 *
	 * @param   string  $id  An ID for the registry instance
	 *
	 * @return  Registry  The Registry object.
	 *
	 * @since   1.0
	 * @deprecated  2.0  Instantiate a new Registry instance instead
	 */
	public static function getInstance($id)
	{
		if (empty(self::$instances[$id]))
		{
			self::$instances[$id] = new self;
		}

		return self::$instances[$id];
	}

	/**
	 * Gets this object represented as an ArrayIterator.
	 *
	 * This allows the data properties to be accessed via a foreach statement.
	 *
	 * @return  \ArrayIterator  This object represented as an ArrayIterator.
	 *
	 * @see     IteratorAggregate::getIterator()
	 * @since   1.3.0
	 */
	public function getIterator()
	{
		return new \ArrayIterator($this->data);
	}

	/**
	 * Load an associative array of values into the default namespace
	 *
	 * @param   array    $array      Associative array of value to load
	 * @param   boolean  $flattened  Load from a one-dimensional array
	 * @param   string   $separator  The key separator
	 *
	 * @return  Registry  Return this object to support chaining.
	 *
	 * @since   1.0
	 */
	public function loadArray($array, $flattened = false, $separator = null)
	{
		if (!$flattened)
		{
			$this->bindData($this->data, $array);

			return $this;
		}

		foreach ($array as $k => $v)
		{
			$this->set($k, $v, $separator);
		}

		return $this;
	}

	/**
	 * Load the public variables of the object into the default namespace.
	 *
	 * @param   object  $object  The object holding the publics to load
	 *
	 * @return  Registry  Return this object to support chaining.
	 *
	 * @since   1.0
	 */
	public function loadObject($object)
	{
		$this->bindData($this->data, $object);

		return $this;
	}

	/**
	 * Load the contents of a file into the registry
	 *
	 * @param   string  $file     Path to file to load
	 * @param   string  $format   Format of the file [optional: defaults to JSON]
	 * @param   array   $options  Options used by the formatter
	 *
	 * @return  Registry  Return this object to support chaining.
	 *
	 * @since   1.0
	 */
	public function loadFile($file, $format = 'JSON', $options = array())
	{
		$data = file_get_contents($file);

		return $this->loadString($data, $format, $options);
	}

	/**
	 * Load a string into the registry
	 *
	 * @param   string  $data     String to load into the registry
	 * @param   string  $format   Format of the string
	 * @param   array   $options  Options used by the formatter
	 *
	 * @return  Registry  Return this object to support chaining.
	 *
	 * @since   1.0
	 */
	public function loadString($data, $format = 'JSON', $options = array())
	{
		// Load a string into the given namespace [or default namespace if not given]
		$handler = AbstractRegistryFormat::getInstance($format, $options);

		$obj = $handler->stringToObject($data, $options);

		// If the data object has not yet been initialized, direct assign the object
		if (!$this->initialized)
		{
			$this->data        = $obj;
			$this->initialized = true;

			return $this;
		}

		$this->loadObject($obj);

		return $this;
	}

	/**
	 * Merge a Registry object into this one
	 *
	 * @param   Registry  $source     Source Registry object to merge.
	 * @param   boolean   $recursive  True to support recursive merge the children values.
	 *
	 * @return  Registry|false  Return this object to support chaining or false if $source is not an instance of Registry.
	 *
	 * @since   1.0
	 */
	public function merge($source, $recursive = false)
	{
		if (!$source instanceof Registry)
		{
			return false;
		}

		$this->bindData($this->data, $source->toArray(), $recursive, false);

		return $this;
	}

	/**
	 * Method to extract a sub-registry from path
	 *
	 * @param   string  $path  Registry path (e.g. joomla.content.showauthor)
	 *
	 * @return  Registry|null  Registry object if data is present
	 *
	 * @since   1.2.0
	 */
	public function extract($path)
	{
		$data = $this->get($path);

		if ($data === null)
		{
			return null;
		}

		return new Registry($data);
	}

	/**
	 * Checks whether an offset exists in the iterator.
	 *
	 * @param   mixed  $offset  The array offset.
	 *
	 * @return  boolean  True if the offset exists, false otherwise.
	 *
	 * @since   1.0
	 */
	public function offsetExists($offset)
	{
		return (boolean) ($this->get($offset) !== null);
	}

	/**
	 * Gets an offset in the iterator.
	 *
	 * @param   mixed  $offset  The array offset.
	 *
	 * @return  mixed  The array value if it exists, null otherwise.
	 *
	 * @since   1.0
	 */
	public function offsetGet($offset)
	{
		return $this->get($offset);
	}

	/**
	 * Sets an offset in the iterator.
	 *
	 * @param   mixed  $offset  The array offset.
	 * @param   mixed  $value   The array value.
	 *
	 * @return  void
	 *
	 * @since   1.0
	 */
	public function offsetSet($offset, $value)
	{
		$this->set($offset, $value);
	}

	/**
	 * Unsets an offset in the iterator.
	 *
	 * @param   mixed  $offset  The array offset.
	 *
	 * @return  void
	 *
	 * @since   1.0
	 */
	public function offsetUnset($offset)
	{
		$this->remove($offset);
	}

	/**
	 * Set a registry value.
	 *
	 * @param   string  $path       Registry Path (e.g. joomla.content.showauthor)
	 * @param   mixed   $value      Value of entry
	 * @param   string  $separator  The key separator
	 *
	 * @return  mixed  The value of the that has been set.
	 *
	 * @since   1.0
	 */
	public function set($path, $value, $separator = null)
	{
		if (empty($separator))
		{
			$separator = $this->separator;
		}

		/*
		 * Explode the registry path into an array and remove empty
		 * nodes that occur as a result of a double separator. ex: joomla..test
		 * Finally, re-key the array so they are sequential.
		 */
		$nodes = array_values(array_filter(explode($separator, $path), 'strlen'));

		if (!$nodes)
		{
			return null;
		}

		// Initialize the current node to be the registry root.
		$node = $this->data;

		// Traverse the registry to find the correct node for the result.
		for ($i = 0, $n = count($nodes) - 1; $i < $n; $i++)
		{
			if (is_object($node))
			{
				if (!isset($node->{$nodes[$i]}) && ($i !== $n))
				{
					$node->{$nodes[$i]} = new \stdClass;
				}

				// Pass the child as pointer in case it is an object
				$node = &$node->{$nodes[$i]};

				continue;
			}

			if (is_array($node))
			{
				if (($i !== $n) && !isset($node[$nodes[$i]]))
				{
					$node[$nodes[$i]] = new \stdClass;
				}

				// Pass the child as pointer in case it is an array
				$node = &$node[$nodes[$i]];
			}
		}

		// Get the old value if exists so we can return it
		switch (true)
		{
			case (is_object($node)):
				$result = $node->{$nodes[$i]} = $value;
				break;

			case (is_array($node)):
				$result = $node[$nodes[$i]] = $value;
				break;

			default:
				$result = null;
				break;
		}

		return $result;
	}

	/**
	 * Append value to a path in registry
	 *
	 * @param   string  $path   Parent registry Path (e.g. joomla.content.showauthor)
	 * @param   mixed   $value  Value of entry
	 *
	 * @return  mixed  The value of the that has been set.
	 *
	 * @since   1.4.0
	 */
	public function append($path, $value)
	{
		$result = null;

		/*
		 * Explode the registry path into an array and remove empty
		 * nodes that occur as a result of a double dot. ex: joomla..test
		 * Finally, re-key the array so they are sequential.
		 */
		$nodes = array_values(array_filter(explode('.', $path), 'strlen'));

		if ($nodes)
		{
			// Initialize the current node to be the registry root.
			$node = $this->data;

			// Traverse the registry to find the correct node for the result.
			// TODO Create a new private method from part of code below, as it is almost equal to 'set' method
			for ($i = 0, $n = count($nodes) - 1; $i <= $n; $i++)
			{
				if (is_object($node))
				{
					if (!isset($node->{$nodes[$i]}) && ($i !== $n))
					{
						$node->{$nodes[$i]} = new \stdClass;
					}

					// Pass the child as pointer in case it is an array
					$node = &$node->{$nodes[$i]};
				}
				elseif (is_array($node))
				{
					if (($i !== $n) && !isset($node[$nodes[$i]]))
					{
						$node[$nodes[$i]] = new \stdClass;
					}

					// Pass the child as pointer in case it is an array
					$node = &$node[$nodes[$i]];
				}
			}

			if (!is_array($node))
				// Convert the node to array to make append possible
			{
				$node = get_object_vars($node);
			}

			$node[] = $value;
			$result = $value;
		}

		return $result;
	}

	/**
	 * Delete a registry value
	 *
	 * @param   string  $path  Registry Path (e.g. joomla.content.showauthor)
	 *
	 * @return  mixed  The value of the removed node or null if not set
	 *
	 * @since   1.6.0
	 */
	public function remove($path)
	{
		// Cheap optimisation to direct remove the node if there is no separator
		if (!strpos($path, $this->separator))
		{
			$result = (isset($this->data->$path) && $this->data->$path !== null && $this->data->$path !== '') ? $this->data->$path : null;

			unset($this->data->$path);

			return $result;
		}

		/*
		 * Explode the registry path into an array and remove empty
		 * nodes that occur as a result of a double separator. ex: joomla..test
		 * Finally, re-key the array so they are sequential.
		 */
		$nodes = array_values(array_filter(explode($this->separator, $path), 'strlen'));

		if (!$nodes)
		{
			return null;
		}

		// Initialize the current node to be the registry root.
		$node   = $this->data;
		$parent = null;

		// Traverse the registry to find the correct node for the result.
		for ($i = 0, $n = count($nodes) - 1; $i < $n; $i++)
		{
			if (is_object($node))
			{
				if (!isset($node->{$nodes[$i]}) && ($i !== $n))
				{
					continue;
				}

				$parent = &$node;
				$node   = $node->{$nodes[$i]};

				continue;
			}

			if (is_array($node))
			{
				if (($i !== $n) && !isset($node[$nodes[$i]]))
				{
					continue;
				}

				$parent = &$node;
				$node   = $node[$nodes[$i]];

				continue;
			}
		}

		// Get the old value if exists so we can return it
		switch (true)
		{
			case (is_object($node)):
				$result = isset($node->{$nodes[$i]}) ? $node->{$nodes[$i]} : null;
				unset($parent->{$nodes[$i]});
				break;

			case (is_array($node)):
				$result = isset($node[$nodes[$i]]) ? $node[$nodes[$i]] : null;
				unset($parent[$nodes[$i]]);
				break;

			default:
				$result = null;
				break;
		}

		return $result;
	}

	/**
	 * Transforms a namespace to an array
	 *
	 * @return  array  An associative array holding the namespace data
	 *
	 * @since   1.0
	 */
	public function toArray()
	{
		return (array) $this->asArray($this->data);
	}

	/**
	 * Transforms a namespace to an object
	 *
	 * @return  object   An an object holding the namespace data
	 *
	 * @since   1.0
	 */
	public function toObject()
	{
		return $this->data;
	}

	/**
	 * Get a namespace in a given string format
	 *
	 * @param   string  $format   Format to return the string in
	 * @param   mixed   $options  Parameters used by the formatter, see formatters for more info
	 *
	 * @return  string   Namespace in string format
	 *
	 * @since   1.0
	 */
	public function toString($format = 'JSON', $options = array())
	{
		// Return a namespace in a given format
		$handler = AbstractRegistryFormat::getInstance($format, $options);

		return $handler->objectToString($this->data, $options);
	}

	/**
	 * Method to recursively bind data to a parent object.
	 *
	 * @param   object   $parent     The parent object on which to attach the data values.
	 * @param   mixed    $data       An array or object of data to bind to the parent object.
	 * @param   boolean  $recursive  True to support recursive bindData.
	 * @param   boolean  $allowNull  True to allow null values.
	 *
	 * @return  void
	 *
	 * @since   1.0
	 */
	protected function bindData($parent, $data, $recursive = true, $allowNull = true)
	{
		// The data object is now initialized
		$this->initialized = true;

		// Ensure the input data is an array.
		$data = is_object($data) ? get_object_vars($data) : (array) $data;

		foreach ($data as $k => $v)
		{
			if (!$allowNull && !(($v !== null) && ($v !== '')))
			{
				continue;
			}

			if ($recursive && ((is_array($v) && ArrayHelper::isAssociative($v)) || is_object($v)))
			{
				if (!isset($parent->$k))
				{
					$parent->$k = new \stdClass;
				}

				$this->bindData($parent->$k, $v);

				continue;
			}

			$parent->$k = $v;
		}
	}

	/**
	 * Method to recursively convert an object of data to an array.
	 *
	 * @param   object  $data  An object of data to return as an array.
	 *
	 * @return  array  Array representation of the input object.
	 *
	 * @since   1.0
	 */
	protected function asArray($data)
	{
		$array = array();

		if (is_object($data))
		{
			$data = get_object_vars($data);
		}

		foreach ($data as $k => $v)
		{
			if (is_object($v) || is_array($v))
			{
				$array[$k] = $this->asArray($v);

				continue;
			}

			$array[$k] = $v;
		}

		return $array;
	}

	/**
	 * Dump to one dimension array.
	 *
	 * @param   string  $separator  The key separator.
	 *
	 * @return  string[]  Dumped array.
	 *
	 * @since   1.3.0
	 */
	public function flatten($separator = null)
	{
		$array = array();

		if (empty($separator))
		{
			$separator = $this->separator;
		}

		$this->toFlatten($separator, $this->data, $array);

		return $array;
	}

	/**
	 * Method to recursively convert data to one dimension array.
	 *
	 * @param   string        $separator  The key separator.
	 * @param   array|object  $data       Data source of this scope.
	 * @param   array         $array      The result array, it is passed by reference.
	 * @param   string        $prefix     Last level key prefix.
	 *
	 * @return  void
	 *
	 * @since   1.3.0
	 */
	protected function toFlatten($separator = null, $data = null, &$array = array(), $prefix = '')
	{
		$data = (array) $data;

		if (empty($separator))
		{
			$separator = $this->separator;
		}

		foreach ($data as $k => $v)
		{
			$key = $prefix ? $prefix . $separator . $k : $k;

			if (is_object($v) || is_array($v))
			{
				$this->toFlatten($separator, $v, $array, $key);

				continue;
			}

			$array[$key] = $v;
		}
	}
}

Registry file in question here

Don't really need the file contents inline here. If it doesn't match what's in this repository then it's clearly going to be wrong but if that happens that's a sign that your previous update didn't go as expected.

Registry::set() hasn't changed for all practical purposes in quite some time. Same for Session::set(). And the fact that it started "after two weeks from updating to 3.8.10" to me points to this not being a core issue, because if it were one then it would've been immediately evident and it would've been reported multiple times by now. To me really smells like there is some extension creating havoc on your platform.

@nronline Please run this script - read the instructions and use including core=1 parameter. For reference this script is from @Kubik-Rubik.

Agreed, however it's weird as no changes have been made to production since then. Also the same upgrade using the same files was implemented on dev beforehand and everything is fine so odd.

I will try replacing the corrupted directories and see if this solves the problem. Failing that the typical one by one disabling of extensions :) Thanks for your help with this guys

@nronline see #21381 (comment)

The file you just posted as being on your server is NOT the one distributed by joomla. You can easily tell that because in your file thetag is written
@SInCE
when it should be
@SInCE
I suspect there will therefore be other changes as well and it points to your live site having been exploited.

I am therefore closing this as it is an issue specific to your site and not general to joomla.

The @since tag thing is because there is a user on GitHub with that username and @ mentions reformat the username to however they formatted their username. So you HAVE to wrap those things in code blocks to get it right.

I stand corrected then but i still don't see that this will be a core issue

Hi guys, I managed to resolve the issue with the help of the client. There was nothing wrong with the Joomla installation at all. It related to some kind of server issue and was resolved by a simple restart.

I am waiting for feedback on the specifics from the client as they are still investigating.
Thanks for your time on this

@nronline Post here specifics of the server issue after you receive it from the client if you can.