Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <CAFcO6XPbh8JSYktdb4HstBunmsUfj-28hAT=qhU+AC0Z7UxBog@mail.gmail.com>
Date: Thu, 3 Dec 2020 10:41:11 +0800
From: butt3rflyh4ck <butterflyhuangxx@...il.com>
To: oss-security@...ts.openwall.com
Subject: Re: Linux Kernel: ALSA: use-after-free Write in snd_rawmidi_kernel_write1

Hi,
this was assigned CVE-2020-27786 via Red Hat.


Regards.
 butt3rflyh4ck.

 butt3rflyh4ck.




On Tue, Dec 1, 2020 at 1:51 PM butt3rflyh4ck <butterflyhuangxx@...il.com> wrote:
>
> Hi,
> I reported a use-after-free bug in snd_rawmidi_kernel_write1 in sound/core/rawmidi.c months ago. And I reproduced it in the latest version linux-5.7.0 at that time.
>
> Description:
>
> It was found that the raw midi kernel driver does not protect
> against concurrent access which leads to a use-after-free in snd_rawmidi_kernel_read1() and snd_rawmidi_kernel_write1() in rawmidi.c file.
> A malicious local attacker could possibly use this for privilege escalation.
>
> Root Cause:
>
> The rawmidi core allows user to resize the runtime buffer via ioctl,
> and this may lead to UAF when performed during concurrent reads or writes: the read/write functions unlock the runtime lock temporarily during copying form/to user-space,
> and that's the race window.
>
> Patch for this issue:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c1f6e3c818dd734c30f6a7eeebf232ba2cf3181d
>
> CVE assigned:
>
> not assigned.
>
> Timeline:
>
> *2020/5/7  - Vulnerability reported to security@...nel.org.
> *2020/5/7  - Vulnerability confirmed and patched.
> *2020/5/18 - Request a CVE ID via https://cveform.mitre.org/
> *2020/11/18 - CVE Request responded but not assigned.
> *2020/11/18 - Reported to Red Hat.
> *2020/12/1 - Opened on oss -security@...ts.openwall.com
>
> Credit:
>
> This issue was discovered by the ADLab of venustech.
>
>
> Regards.
>  butt3rflyh4ck.

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.