| From e13a342c079aeb73e31dfa19eaca119761bac3f3 Mon Sep 17 00:00:00 2001 |
| From: Jonas Meurer <jonas@freesources.org> |
| Date: Tue, 11 Jun 2019 12:16:46 +0200 |
| Subject: [PATCH] Fix #501: Uninitialized read in gdImageCreateFromXbm |
| (CVE-2019-11038) |
| |
| Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2019-11038 |
| Bug-Debian: https://bugs.debian.org/929821 |
| Bug: https://github.com/libgd/libgd/issues/501 |
| |
| We have to ensure that `sscanf()` does indeed read a hex value here, |
| and bail out otherwise. |
| |
| Original patch by Christoph M. Becker <cmbecker69@gmx.de> for PHP libgd ext. |
| https://git.php.net/?p=php-src.git;a=commit;h=ed6dee9a198c904ad5e03113e58a2d2c200f5184 |
| |
| Signed-off-by: Peter Korsgaard <peter@korsgaard.com> |
| --- |
| src/gd_xbm.c | 6 +++++- |
| 1 file changed, 5 insertions(+), 1 deletion(-) |
| |
| diff --git a/src/gd_xbm.c b/src/gd_xbm.c |
| index 4ca41ac..cf0545e 100644 |
| --- a/src/gd_xbm.c |
| +++ b/src/gd_xbm.c |
| @@ -169,7 +169,11 @@ BGD_DECLARE(gdImagePtr) gdImageCreateFromXbm(FILE * fd) |
| } |
| h[3] = ch; |
| } |
| - sscanf(h, "%x", &b); |
| + if (sscanf(h, "%x", &b) != 1) { |
| + gd_error("invalid XBM"); |
| + gdImageDestroy(im); |
| + return 0; |
| + } |
| for (bit = 1; bit <= max_bit; bit = bit << 1) { |
| gdImageSetPixel(im, x++, y, (b & bit) ? 1 : 0); |
| if (x == im->sx) { |
| -- |
| 2.20.1 |
| |
