Fix CVE-2026-58014: heap under-read in g_key_file_get_locale_string_list

Backport upstream commit 5f6d86b50bebf5458ab1becf4de2c5e5f066122b
to fix CVE-2026-58014, a one-byte heap under-read in
g_key_file_get_locale_string_list() when called on a key with
an empty value. The fix adds a `len > 0` guard before accessing
value[len-1]. The patch also includes a unit test and fuzzing
test enhancement.

CVE: CVE-2026-58014
Upstream patches:
 - 5f6d86b50b.patch
Resolves: RHEL-190604

This commit was backported by Ymir, a Red Hat Enterprise Linux software maintenance AI agent.

Assisted-by: Ymir
This commit is contained in:
RHEL Packaging Agent 2026-08-19 16:32:47 +00:00
parent 5cb1f83ea7
commit 138500dd5a
2 changed files with 109 additions and 1 deletions

101
CVE-2026-58014.patch Normal file
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@ -0,0 +1,101 @@
From 2303fbb163c76f3b07d0ff3ba3c1b806bb94b780 Mon Sep 17 00:00:00 2001
From: Philip Withnall <pwithnall@gnome.org>
Date: Sat, 11 Apr 2026 14:42:57 +0100
Subject: [PATCH] gkeyfile: Fix a one-byte heap under-read with
g_key_file_get_locale_string_list()
If this method was called on a key file key which has an empty value,
`len == 0` and this leads to a one-byte under-read off the start of the
key file buffer.
Spotted by linhlhq as #YWH-PGM9867-200. The suggested fix is theirs, and
the unit test is adapted from their report. I added the fuzzing test.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Fixes: #3930
---
fuzzing/fuzz_key.c | 9 +++++++++
glib/gkeyfile.c | 2 +-
glib/tests/keyfile.c | 23 +++++++++++++++++++++++
3 files changed, 33 insertions(+), 1 deletion(-)
diff --git a/fuzzing/fuzz_key.c b/fuzzing/fuzz_key.c
index 9f1f9187e..285bad26f 100644
--- a/fuzzing/fuzz_key.c
+++ b/fuzzing/fuzz_key.c
@@ -6,11 +6,20 @@ test_parse (const gchar *data,
GKeyFileFlags flags)
{
GKeyFile *key = NULL;
+ char *comment = NULL;
+ char **list = NULL;
key = g_key_file_new ();
g_key_file_load_from_data (key, (const gchar*) data, size, G_KEY_FILE_NONE,
NULL);
+ /* Also try some additional parsing and see if it crashes */
+ comment = g_key_file_get_comment (key, "group", "key", NULL);
+ g_free (comment);
+
+ list = g_key_file_get_locale_string_list (key, "group", "key", "de", NULL, NULL);
+ g_strfreev (list);
+
g_key_file_free (key);
}
diff --git a/glib/gkeyfile.c b/glib/gkeyfile.c
index 0b58edb3f..aae03afb0 100644
--- a/glib/gkeyfile.c
+++ b/glib/gkeyfile.c
@@ -2409,7 +2409,7 @@ g_key_file_get_locale_string_list (GKeyFile *key_file,
}
len = strlen (value);
- if (value[len - 1] == key_file->list_separator)
+ if (len > 0 && value[len - 1] == key_file->list_separator)
value[len - 1] = '\0';
list_separator[0] = key_file->list_separator;
diff --git a/glib/tests/keyfile.c b/glib/tests/keyfile.c
index 975ef8167..215c973a5 100644
--- a/glib/tests/keyfile.c
+++ b/glib/tests/keyfile.c
@@ -800,6 +800,28 @@ test_locale_string_multiple_loads (void)
g_free (old_locale);
}
+static void
+test_locale_string_empty (void)
+{
+ GKeyFile *keyfile = NULL;
+ GError *local_error = NULL;
+ const char *data =
+ "[valid]\n"
+ "key1=\n";
+
+ g_test_summary ("Check that loading an empty translatable string works");
+ g_test_bug ("https://gitlab.gnome.org/GNOME/glib/-/issues/3930");
+
+ keyfile = g_key_file_new ();
+
+ g_key_file_load_from_data (keyfile, data, -1, G_KEY_FILE_NONE, &local_error);
+ g_assert_no_error (local_error);
+
+ check_locale_string_list_value (keyfile, "valid", "key1", NULL, NULL);
+
+ g_key_file_free (keyfile);
+}
+
static void
test_lists (void)
{
@@ -1834,6 +1856,7 @@ main (int argc, char *argv[])
g_test_add_func ("/keyfile/number", test_number);
g_test_add_func ("/keyfile/locale-string", test_locale_string);
g_test_add_func ("/keyfile/locale-string/multiple-loads", test_locale_string_multiple_loads);
+ g_test_add_func ("/keyfile/locale-string/empty", test_locale_string_empty);
g_test_add_func ("/keyfile/lists", test_lists);
g_test_add_func ("/keyfile/lists-set-get", test_lists_set_get);
g_test_add_func ("/keyfile/group-remove", test_group_remove);

View File

@ -1,6 +1,6 @@
Name: glib2
Version: 2.68.4
Release: 28%{?dist}
Release: 29%{?dist}
Summary: A library of handy utility functions
License: LGPLv2+
@ -116,6 +116,9 @@ Patch: CVE-2026-15588.patch
# https://gitlab.gnome.org/GNOME/glib/-/commit/8b72ad09c874ddff122b3e67b3470c5e2eab7690
Patch: CVE-2026-58015.patch
# https://gitlab.gnome.org/GNOME/glib/-/commit/5f6d86b50bebf5458ab1becf4de2c5e5f066122b
Patch: CVE-2026-58014.patch
BuildRequires: chrpath
BuildRequires: gcc
BuildRequires: gcc-c++
@ -337,6 +340,10 @@ glib-compile-schemas %{_datadir}/glib-2.0/schemas &> /dev/null || :
%{_datadir}/installed-tests
%changelog
* Wed Aug 19 2026 RHEL Packaging Agent <redhat-ymir-agent@redhat.com> - 2.68.4-29
- Fix CVE-2026-58014: heap under-read in g_key_file_get_locale_string_list
Resolves: RHEL-190604
* Wed Aug 19 2026 RHEL Packaging Agent <redhat-ymir-agent@redhat.com> - 2.68.4-28
- Fix CVE-2026-58015: validate D-Bus DBUS_COOKIE_SHA1 cookie context
Resolves: RHEL-212262