diff --git a/main.c b/main.c
index da862742..642bea23 100644
--- a/main.c
+++ b/main.c
@@ -818,6 +818,7 @@ out:
     if (term.kbd.xkb != NULL)
         xkb_context_unref(term.kbd.xkb);
 
+    free(term.vt.osc.data);
     for (int row = 0; row < term.normal.num_rows; row++)
         grid_row_free(term.normal.rows[row]);
     free(term.normal.rows);
diff --git a/osc.c b/osc.c
index 5697b230..21ee67c0 100644
--- a/osc.c
+++ b/osc.c
@@ -83,3 +83,23 @@ osc_dispatch(struct terminal *term)
         break;
     }
 }
+
+bool
+osc_ensure_size(struct terminal *term, size_t required_size)
+{
+    if (required_size <= term->vt.osc.size)
+        return true;
+
+    size_t new_size = (required_size + 127) / 128 * 128;
+    assert(new_size > 0);
+
+    uint8_t *new_data = realloc(term->vt.osc.data, new_size);
+    if (new_data == NULL) {
+        LOG_ERRNO("failed to increase size of OSC buffer");
+        return false;
+    }
+
+    term->vt.osc.data = new_data;
+    term->vt.osc.size = new_size;
+    return true;
+}
diff --git a/osc.h b/osc.h
index 9b0b8328..1a40116b 100644
--- a/osc.h
+++ b/osc.h
@@ -3,4 +3,5 @@
 #include <stdbool.h>
 #include "terminal.h"
 
+bool osc_ensure_size(struct terminal *term, size_t size);
 void osc_dispatch(struct terminal *term);
diff --git a/terminal.h b/terminal.h
index 8bfc3918..57e8c97a 100644
--- a/terminal.h
+++ b/terminal.h
@@ -125,7 +125,8 @@ struct vt {
     } params;
     char private;
     struct {
-        uint8_t data[1024];
+        uint8_t *data;
+        size_t size;
         size_t idx;
     } osc;
     struct {
diff --git a/vt.c b/vt.c
index 3ce99250..8899fc74 100644
--- a/vt.c
+++ b/vt.c
@@ -909,12 +909,15 @@ action(struct terminal *term, enum action _action, uint8_t c)
         break;
 
     case ACTION_OSC_PUT:
-        if (term->vt.osc.idx < (int)sizeof(term->vt.osc.data) - 1)
-            term->vt.osc.data[term->vt.osc.idx++] = c;
+        if (!osc_ensure_size(term, term->vt.osc.idx + 1))
+            break;
+
+        term->vt.osc.data[term->vt.osc.idx++] = c;
         break;
 
     case ACTION_OSC_END:
-        assert(term->vt.osc.idx < sizeof(term->vt.osc.data));
+        if (!osc_ensure_size(term, term->vt.osc.idx + 1))
+            break;
         term->vt.osc.data[term->vt.osc.idx] = '\0';
         osc_dispatch(term);
         break;