oss-sec mailing list archives
Re: Varnish - no CVE == bug regression
From: Kurt Seifried <kseifried () redhat com>
Date: Thu, 03 Jul 2014 13:41:58 -0600
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 03/07/14 11:12 AM, Stefan Bühler wrote:
On Thu, 3 Jul 2014 08:15:06 +0000 Sven Kieske <S.Kieske () mittwald de> wrote:-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I'd agree with this. And I don't get the argument from poul-henning kamp, what I understand is: "hey, we trust our backend server" well, but your backend server can make you crash, so you probably shouldn't trust it in the first place? you _never_ can trust input, so you have to validate it, either way, at least enough to not crash or perform malicious actions. Am 03.07.2014 09:48, schrieb Kurt Seifried:So as I understand this: Varnish front end for web servers, the web servers can trigger varnish to restart. Are the back end servers supposed to be able to cause varnish to restart? I'm guessing not. Scenario: hosting env, or a website with a vuln, whatever, you can now cause the varnish front ends to restart constantly, effectively causing a permanent denial of service. That sounds CVE worthy. Or am I missing something?you should never trust *untrusted* input. your root shell usually trusts the input it gets... so the valgrind developers decided that they consider the backend webservers trusted, at least regarding the capability to cause a DoS. for the record - so does lighttpd (a backend can trigger OOM as lighty reads (nearly) as fast as possible from a backend, as backends often only handle one request at a time); we usually tell people to use X-sendfile instead of sending ISOs through php.
That also sounds like it needs a CVE then. You should not be able to trivially DoS stuff, especially OOM, things should protect themselves from OOM'ing especially if they accept user controlled input from the network.
just because you disagree with such decisions doesn't make it CVE worthy (missing or wrong documentation could).
So to be clear your argument is that the http backends serviced by Varnish are supposed to be able to shut down Varnish, not by using an administrative channel/command but by executing a denial of service against Varnish? And that this is intended behaviour and thus not a security vulnerability?
in case you actually want to assign a CVE here, maybe we can get one for the bad openssl default cipherstring too? because for that it is really obvious that it is f*** wrong, but i think that none was assigned because upstream didn't agree with it. regards, Stefan
- -- Kurt Seifried -- Red Hat -- Product Security -- Cloud PGP A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQIcBAEBAgAGBQJTtbIDAAoJEBYNRVNeJnmT/mkQAMmXrwXn4+Y/hGUGMfp3anFo 7NVLg+50up/BhuVQ5fOA/EYClDQZNWSg8PrQWvo8cxwCtJOsXVFEHmG+2f7xNKkv rCN97rMVz448hoFSHq5qwtWcZw/V8/A13hlAclDA7f7p+/B57Pok7igOciGwLbJb zGXeODwFnHlX+eOZgn/hDt0FzG5n1cCHrnK4NgIT/yLSYDI5O235/0g999ooDrn7 FwiOFxdnjkveBkcGde6VJ4TlyqA9qoYJ2S4t/fkvM9j/vXvag+V0wwSdDkpZuFNZ ycERIVWZW6hnr7aZ/G76Rie2E4LY8B0T9cJF9pTA7FkJWF2Yg8LbPHz5jSH1cQuZ bOanZXE8bPLAdLHKU0JWbDPYDdhjEk8mgLbbskSmMxslmygw9Z5kceUoug2Y75Xs LRcpOuv08b3QO3wJNV6Z8fbkOYcdeTJPRmNLYrWoPqJHx8jWZzaUq1d1T8YGqos/ V1KiFzDKH8Yw+yjmYAe+8DXpiOUH90yMYC8d8ewsipDXNNVHhyVUTeV/bNYT+0Gn MU0GGSd90eLCC+czkw/tgY/XHIE0ycLeWDgTBUYkfOZ4UjgscMF6R5jcuJGMP71L ftBbGNXduNHLkXL3GFUII+fAWQpWn14usmZZTHsoecmOoBPUV9paRuGBtzPmz+xJ vHDLLMP7/qSLN88zY2d0 =7hmC -----END PGP SIGNATURE-----
Current thread:
- Varnish - no CVE == bug regression Marek Kroemeke (Jul 02)
- Re: Varnish - no CVE == bug regression Solar Designer (Jul 02)
- Re: Varnish - no CVE == bug regression Poul-Henning Kamp (Jul 02)
- Re: Varnish - no CVE == bug regression Marek Kroemeke (Jul 02)
- Re: Varnish - no CVE == bug regression Poul-Henning Kamp (Jul 03)
- Re: Varnish - no CVE == bug regression Kurt Seifried (Jul 03)
- Re: Varnish - no CVE == bug regression Sven Kieske (Jul 03)
- Re: Varnish - no CVE == bug regression Stefan Bühler (Jul 03)
- Re: Varnish - no CVE == bug regression Kurt Seifried (Jul 03)
- Re: Varnish - no CVE == bug regression Marek Kroemeke (Jul 03)
- Re: Varnish - no CVE == bug regression Stefan Bühler (Jul 03)
- Re: Varnish - no CVE == bug regression Stefan Bühler (Jul 03)
- Re: Varnish - no CVE == bug regression Kurt Seifried (Jul 03)
- Re: Varnish - no CVE == bug regression Seth Arnold (Jul 03)
- Re: Varnish - no CVE == bug regression Poul-Henning Kamp (Jul 02)
- Re: Varnish - no CVE == bug regression Sven Kieske (Jul 04)
- Re: Varnish - no CVE == bug regression Solar Designer (Jul 02)
- Re: Varnish - no CVE == bug regression Poul-Henning Kamp (Jul 05)
- Re: Varnish - no CVE == bug regression cve-assign (Jul 08)
- Re: Varnish - no CVE == bug regression Poul-Henning Kamp (Jul 08)
- Re: Re: Varnish - no CVE == bug regression Michael Samuel (Jul 08)