Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [day] [month] [year] [list]
Date: Mon, 10 Jul 2017 09:12:19 +0000
From: "Agostino Sarubbo" <ago@...too.org>
To: "oss-security@...ts.openwall.com" <oss-security@...ts.openwall.com>
Subject: xar: NULL pointer dereference in xar_get_path (util.c)

Description:
xar is an easily extensible archive format.

The complete ASan output of the issue:

# xar -t -f $FILE
==5525==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x7f075cfb35f6 bp 0x7fff705167b0 sp 0x7fff70515f38 T0)
==5525==The signal is caused by a READ memory access.
==5525==Hint: address points to the zero page.
    #0 0x7f075cfb35f5 in strlen /tmp/portage/sys-libs/glibc-2.23-r3/work/glibc-2.23/string/../sysdeps/x86_64/strlen.S:76
    #1 0x45f5ef in __strdup /tmp/portage/sys-libs/compiler-rt-sanitizers-4.0.0/work/compiler-rt-4.0.0.src/lib/asan/asan_interceptors.cc:562
    #2 0x7f075decebc8 in xar_get_path /var/tmp/portage/app-arch/xar-1.6.1-r1/work/xar-1.6.1/lib/util.c:95:8
    #3 0x523f93 in print_file /var/tmp/portage/app-arch/xar-1.6.1-r1/work/xar-1.6.1/src/xar.c:214:16
    #4 0x513f07 in list /var/tmp/portage/app-arch/xar-1.6.1-r1/work/xar-1.6.1/src/xar.c:1524:4
    #5 0x513f07 in main /var/tmp/portage/app-arch/xar-1.6.1-r1/work/xar-1.6.1/src/xar.c:2666
    #6 0x7f075cf55680 in __libc_start_main /tmp/portage/sys-libs/glibc-2.23-r3/work/glibc-2.23/csu/../csu/libc-start.c:289
    #7 0x41af38 in _init (/usr/bin/xar+0x41af38)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /tmp/portage/sys-libs/glibc-2.23-r3/work/glibc-2.23/string/../sysdeps/x86_64/strlen.S:76 in strlen
==5525==ABORTING
Affected version:
1.6.1

Fixed version:
N/A

Commit fix:
N/A

Credit:
This bug was discovered by Agostino Sarubbo of Gentoo.

CVE:
CVE-2017-11125

Reproducer:
https://github.com/asarubbo/poc/blob/master/00287-xar-nullptr-xar_get_path

Timeline:
2017-06-17: bug discovered and reported to upstream
2017-06-28: blog post about the issue
2017-07-10: CVE assigned

Note:
This bug was found with American Fuzzy Lop.

Permalink:
https://blogs.gentoo.org/ago/2017/06/28/xar-null-pointer-dereference-in-xar_get_path-util-c/

--
Agostino Sarubbo
Gentoo Linux Developer


Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.