From: VanshAgarwal24036 <148854295+VanshAgarwal24036@users.noreply.github.com>
Date: Mon, 12 Jan 2026 15:39:32 +0000 (+0530)
Subject: gh-143544: Fix possible use-after-free in the JSON decoder when JSONDecodeError disap... 
X-Git-Tag: v3.15.0a5~11^2~26
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=c3157480601499565fd42a8afbdb0207328ac484;p=thirdparty%2FPython%2Fcpython.git

gh-143544: Fix possible use-after-free in the JSON decoder when JSONDecodeError disappears during raising it (#143561)

Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
---

diff --git a/Modules/_json.c b/Modules/_json.c
index 14714d4b3465..78a85496575a 100644
--- a/Modules/_json.c
+++ b/Modules/_json.c
@@ -423,11 +423,12 @@ raise_errmsg(const char *msg, PyObject *s, Py_ssize_t end)
 
     PyObject *exc;
     exc = PyObject_CallFunction(JSONDecodeError, "zOn", msg, s, end);
-    Py_DECREF(JSONDecodeError);
     if (exc) {
         PyErr_SetObject(JSONDecodeError, exc);
         Py_DECREF(exc);
     }
+
+    Py_DECREF(JSONDecodeError);
 }
 
 static void