diff --git a/src/nvim/decoration.c b/src/nvim/decoration.c
index cc903d8ed5..f83d7fa85e 100644
--- a/src/nvim/decoration.c
+++ b/src/nvim/decoration.c
@@ -417,7 +417,9 @@ void decor_redraw_signs(buf_T *buf, int row, int *num_signs, SignTextAttrs sattr
         if (sattrs[j - 1].priority >= decor->priority) {
           break;
         }
-        sattrs[j] = sattrs[j - 1];
+        if (j < SIGN_SHOW_MAX) {
+          sattrs[j] = sattrs[j - 1];
+        }
       }
       if (j < SIGN_SHOW_MAX) {
         sattrs[j] = (SignTextAttrs) {
diff --git a/test/functional/ui/decorations_spec.lua b/test/functional/ui/decorations_spec.lua
index add3f922c6..5530d3f2f6 100644
--- a/test/functional/ui/decorations_spec.lua
+++ b/test/functional/ui/decorations_spec.lua
@@ -10,6 +10,7 @@ local expect_events = helpers.expect_events
 local meths = helpers.meths
 local curbufmeths = helpers.curbufmeths
 local command = helpers.command
+local assert_alive = helpers.assert_alive
 
 describe('decorations providers', function()
   local screen
@@ -80,7 +81,7 @@ describe('decorations providers', function()
       local ns2 = api.nvim_create_namespace "ns2"
       api.nvim_set_decoration_provider(ns2, {})
     ]])
-    helpers.assert_alive()
+    assert_alive()
   end)
 
   it('leave a trace', function()
@@ -1075,7 +1076,7 @@ end]]
       {1:~                                                 }|
                                                         |
     ]]}
-    helpers.assert_alive()
+    assert_alive()
   end)
 
   it('conceal #19007', function()
@@ -2282,8 +2283,8 @@ l5
     insert(example_text)
     feed 'gg'
 
-    helpers.command('sign define Oldsign text=O3')
-    helpers.command([[exe 'sign place 42 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command('sign define Oldsign text=O3')
+    command([[exe 'sign place 42 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
 
     meths.buf_set_extmark(0, ns, 0, -1, {sign_text='S4', priority=100})
     meths.buf_set_extmark(0, ns, 0, -1, {sign_text='S2', priority=5})
@@ -2306,6 +2307,39 @@ l5
     ]]}
   end)
 
+  it('does not overflow with many old signs #23852', function()
+    screen:try_resize(20, 3)
+
+    command('set signcolumn:auto:9')
+    command('sign define Oldsign text=O3')
+    command([[exe 'sign place 01 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command([[exe 'sign place 02 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command([[exe 'sign place 03 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command([[exe 'sign place 04 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command([[exe 'sign place 05 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command([[exe 'sign place 06 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command([[exe 'sign place 07 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command([[exe 'sign place 08 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    command([[exe 'sign place 09 line=1 name=Oldsign priority=10 buffer=' . bufnr('')]])
+    screen:expect{grid=[[
+      O3O3O3O3O3O3O3O3O3^  |
+      {2:~                   }|
+                          |
+    ]]}
+
+    meths.buf_set_extmark(0, ns, 0, -1, {sign_text='S1', priority=1})
+    screen:expect_unchanged()
+
+    meths.buf_set_extmark(0, ns, 0, -1, {sign_text='S5', priority=200})
+    screen:expect{grid=[[
+      O3O3O3O3O3O3O3O3S5^  |
+      {2:~                   }|
+                          |
+    ]]}
+
+    assert_alive()
+  end)
+
   it('does not set signcolumn for signs without text', function()
     screen:try_resize(20, 3)
     meths.win_set_option(0, 'signcolumn', 'auto')