On Tuesday, February 12, 2019 8:55:18 AM EST Florian Weimer wrote:
That's along the lines of what I was thinking also This looks like more of a
workaround than a root cause fix Without seeing the exploit or a full
discussion of the theory of operation, we really can't pinpoint where the
issue is Was it because of CAP_DAC_OVERRIDE? Is there ...
On 2019-02-13, EJ Campbell <ejc3 () verizonmedia com> wrote:
The privileged user in the container could just un-set the immutable
bit using "/proc/self/fd/" and then open it for writing A read-only
filesystem would work much better
--
Aleksa Sarai
Senior Software Engineer (Containers)
SUSE Linux GmbH
<wwwcypharcom/> ...
On 2019-02-12, Solar Designer <solar () openwall com> wrote:
I have just sent v5 of my AT_THIS_ROOT patchset to LKML[1] -- which
allows userspace processes to block resolution of magic links While
blocking access through /proc/self/exe helps block this issues, being
able to block (from userspace) resolution of all magic links would
massive ...
Hello,
there is a container breakout currently discussed (CVE-2019-5736),
which affected LXC among others Let me share two more, IMHO easier,
breakout techniques that work against LXC, at least in Ubuntu 1810,
which has LXC 303 Both techniques work only in privileged
containers, and so, given that LXC upstream does not treat privileged
contai ...
On 2019-02-13, Aleksa Sarai <cyphar () cyphar com> wrote:
Sorry, I forgot that CAP_LINUX_IMMUTABLE is dropped by default in
Docker Yes that mitigation would also work
--
Aleksa Sarai
Senior Software Engineer (Containers)
SUSE Linux GmbH
<wwwcypharcom/> ...
On 2019-02-12, Steve Grubb <sgrubb () redhat com> wrote:
It's not because of CAP_DAC_OVERRIDE It's just regular DAC As for it
not being a root cause fix, I disagree (it protects against a variety of
concerning attacks that aren't related to this CVE) Obviously if
everyone used correctly-configured user namespaces then this wouldn't be
a ...
Someone outside of the embargo has posted a PoC of the exploit for
CVE-2019-5736 (which is related though not using the same vector)[1]
Since the original researchers have posted a blog post explaining the
exploit in some detail[2], I've decided to post the exploit code early
-- since the cat is out of the bag anyway
CVE-2019-5736tarxz has the ...
While fixing docker / runc is clearly the right fix, would using chattr -i
on runc be a quick mitigation for the issue? I believe that will prevent
the file from being overwritten by the exploit and Etienne Stalmans
verified that it helped:
twittercom/_staaldraad/status/1095354945073754112
(Note I tried top posting this to mailing list a ...
On Tue, Feb 12, 2019 at 12:05:20AM +1100, Aleksa Sarai wrote:
[]
While runc, LXC, and maybe other projects fix CVE-2019-5736 in userspace,
Virtuozzo/OpenVZ 7 has just released a kernel fix instead - please see
the forwarded message below Following links from there, I found the
following description of the issue in context of Virtuozzo and ...
That should have been +i, sorry Thank you for your quick response
EJ
On Wed, Feb 13, 2019 at 1:58 AM Aleksa Sarai <cyphar () cyphar com> wrote: ...
I think that someone already posted a PoC on github, AFAIK
On Wed, Feb 13, 2019 at 1:04 PM Aleksa Sarai <asarai () suse de> wrote: ...
On 2019-02-13, Loganaden Velvindron <loganaden () gmail com> wrote:
Yes, there is a PoC that someone outside of the embargo posted on
GitHub (it is quite different to the one we have but it is using a
related issue which our patch also fixed) At this point I might as well
post the actual exploit code (given that the original vulnerability
...
Severity: Important
Vendor:
The Apache Software Foundation
Versions Affected:
Apache Mesos 140 to 170
The unsupported Apache Mesos pre-140 releases may be also affected
Description:
A specifically crafted Docker image running under the root user can
overwrite the init helper binary of the Mesos container runtime and/or
the Mesos command e ...
NOTE: This advisory was sent to <security-announce () opencontainers org>
two weeks ago If you ship any Open Container Initiative software, we
highly recommend that you subscribe to our security-announce list in
order to receive more timely disclosures of future security issues The
procedure for subscribing to security-announce is outlined ...
Hello Aleksa,
Thank you and others you credit for doing much more than fixing the
immediate issue, and for disclosing this in so much detail
On Thu, Feb 01, 2024 at 07:33:01AM +1100, Aleksa Sarai wrote:
What's setcwd(2)? Perhaps you meant something else?
For reference, here are the threads you started on CVE-2019-5736 and its
exploit bac ...
On 2024-02-01, Solar Designer <solar () openwall com> wrote:
I meant chdir(2), sorry I had getcwd(3) on my mind
That eventually became openat2(2) which was merged in Linux 56
Somewhat ironically, the switch to openat2(2) in runc was the cause of
one of the fd leaks that made this issue exploitable in runc! 😅
However, I later disc ...
On Sat, Jul 06, 2019 at 09:37:37PM +0200, Solar Designer wrote:
Thank you
[snip]
Sure, give me a day or two to get it out I'll cross-post
LKML/ksummit-discuss/oss-security as I think it's one of those times it
actually makes sense
Whatever list admins/members are comfortable with
Yes, this is tricky Maybe "Microsoft Linux Systems G ...
Hi all,
Per our current policy and precedents, I see no valid reasons not to
subscribe Microsoft (or part(s) of it, see below) to linux-distros So
I intend to figure out some detail and proceed with the subscription
The only voiced reasons not to, such as in Georgi Guninski's posting and
in comments on some technology news sites that covered M ...
On Fri, Jun 28, 2019 at 02:57:43PM +0200, Solar Designer wrote:
True, but we care about more than just the kernel side of things
Can I suggest that we fork the discussion around security-bugsrst to
LKML? I can suggest an initial patch to address your comments here but I
think that this is better handled on LKML
My concern with Monday is ...