Add underflow detection to TTF cmap code.

2025-09-06 11:12:05 +02:00 · 2025-08-27 11:21:16 -04:00
parent dc584c0868
commit 410e3b92ea
2 changed files with 7 additions and 1 deletions
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,6 +2,12 @@ Changes in PDFio
 ================


+v1.5.5 - YYYY-MM-DD
+-------------------
+
+- Fixed TTF cmap underflow error.
+
+
 v1.5.4 - 2025-08-26
 -------------------

--- a/ttf.c
+++ b/ttf.c
@@ -1205,7 +1205,7 @@ read_cmap(ttf_t *font)			// I - Font

          /* language = */ read_ushort(font);

-          if (length > (256 + 6))
+          if (length > (256 + 6) || length < 7)
          {
 	    errorf(font, "Bad cmap table length at offset %u.", coffset);
 	    return (false);