Fix use-after-free in json_encode() of a JsonSerializable object#22470
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iliaal wants to merge 1 commit into
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Fix use-after-free in json_encode() of a JsonSerializable object#22470iliaal wants to merge 1 commit into
iliaal wants to merge 1 commit into
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php_json_encode_serializable_object() holds a raw pointer to the object and its recursion guard across the jsonSerialize() call. A user error handler invoked during that call can drop the object's last reference, leaving the post-call recursion-guard clear and the return-value identity check reading freed memory. Pin the object across the call.
Girgias
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Jun 28, 2026
Girgias
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We don't backport these sorts of fuzzer bugs
| <?php | ||
| class Bar implements JsonSerializable { | ||
| public function jsonSerialize(): mixed { | ||
| echo $undefined; |
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Ditto as the other PR: just use trigger_error function
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php_json_encode_serializable_object() keeps the object pointer and its recursion guard live across the jsonSerialize() call. An error handler invoked during that call can drop the object's last reference through an aliased array element, leaving the post-call recursion-guard clear and the return-value identity check reading freed memory. Pin the object across the call. The 8.5 and master encoder dispatches through zend_call_known_function() and gets the same fix in php-src#22469.