CVE-2023-50230: Insufficient Information (NVD-CWE-noinfo)
value: BlueZ Phone Book Access Profile Heap-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of BlueZ. User interaction is required to exploit this vulnerability in that the target must connect to a malicious Bluetooth device.

The specific flaw exists within the handling of the Phone Book Access profile. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-20938.
CWE description: There is insufficient information about the issue to classify it; details are unkown or unspecified.
Published: 2024-05-03T03:16Z
Repository: https://github.com/bluez/bluez
Language: C
Files changed: obexd/client/pbap.c
Commit date: 2023-09-20 14:06:12 -0700
Commit message: pbap: Fix not checking Primary/Secundary Counter length

Primary/Secundary Counters are supposed to be 16 bytes values, if the
server has implemented them incorrectly it may lead to the following
crash:

=================================================================
==31860==ERROR: AddressSanitizer: heap-buffer-overflow on address
0x607000001878 at pc 0x7f95a1575638 bp 0x7fff58c6bb80 sp 0x7fff58c6b328

 READ of size 48 at 0x607000001878 thread T0
     #0 0x7f95a1575637 in MemcmpInterceptorCommon(void*, int (*)(void const*, void const*, unsigned long), void const*, void const*, unsigned long) ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:860
     #1 0x7f95a1575ba6 in __interceptor_memcmp ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:892
     #2 0x7f95a1575ba6 in __interceptor_memcmp ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:887
     #3 0x564df69c77a0 in read_version obexd/client/pbap.c:288
     #4 0x564df69c77a0 in read_return_apparam obexd/client/pbap.c:352
     #5 0x564df69c77a0 in phonebook_size_callback obexd/client/pbap.c:374
     #6 0x564df69bea3c in session_terminate_transfer obexd/client/session.c:921
     #7 0x564df69d56b0 in get_xfer_progress_first obexd/client/transfer.c:729
     #8 0x564df698b9ee in handle_response gobex/gobex.c:1140
     #9 0x564df698cdea in incoming_data gobex/gobex.c:1385
     #10 0x7f95a12fdc43 in g_main_context_dispatch (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x55c43)
     #11 0x7f95a13526c7  (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0xaa6c7)
     #12 0x7f95a12fd2b2 in g_main_loop_run (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x552b2)
     #13 0x564df6977d41 in main obexd/src/main.c:307
     #14 0x7f95a10a7d8f in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
     #15 0x7f95a10a7e3f in __libc_start_main_impl ../csu/libc-start.c:392
     #16 0x564df6978704 in _start (/usr/local/libexec/bluetooth/obexd+0x8b704)
 0x607000001878 is located 0 bytes to the right of 72-byte region [0x607000001830,0x607000001878)

 allocated by thread T0 here:
     #0 0x7f95a1595a37 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
     #1 0x564df69c8b6a in pbap_probe obexd/client/pbap.c:1259

Diff: diff --git a/obexd/client/pbap.c b/obexd/client/pbap.c
index 1ed8c68ecc..2d2aa95089 100644
--- a/obexd/client/pbap.c
+++ b/obexd/client/pbap.c
@@ -283,11 +283,11 @@ static void read_version(struct pbap_data *pbap, GObexApparam *apparam)
 		len = sizeof(value);
 		memset(value, 0, len);
 		data = value;
 	}
 
-	if (memcmp(pbap->primary, data, len)) {
+	if (len == sizeof(pbap->primary) && memcmp(pbap->primary, data, len)) {
 		memcpy(pbap->primary, data, len);
 		g_dbus_emit_property_changed(conn,
 					obc_session_get_path(pbap->session),
 					PBAP_INTERFACE, "PrimaryCounter");
 	}
@@ -297,11 +297,12 @@ static void read_version(struct pbap_data *pbap, GObexApparam *apparam)
 		len = sizeof(value);
 		memset(value, 0, len);
 		data = value;
 	}
 
-	if (memcmp(pbap->secondary, data, len)) {
+	if (len == sizeof(pbap->secondary) &&
+			memcmp(pbap->secondary, data, len)) {
 		memcpy(pbap->secondary, data, len);
 		g_dbus_emit_property_changed(conn,
 					obc_session_get_path(pbap->session),
 					PBAP_INTERFACE, "SecondaryCounter");
 	}

Vulnerable code: 	if (memcmp(pbap->primary, data, len)) {
	if (memcmp(pbap->secondary, data, len)) {
Fixed code: 	if (len == sizeof(pbap->primary) && memcmp(pbap->primary, data, len)) {
	if (len == sizeof(pbap->secondary) &&
			memcmp(pbap->secondary, data, len)) {