Hi Daniel, your frustration is understandable and I hope you excuse a further comment. What is missing, IMVHO, is a central point of reference for all Kamailio security issues. Googling for “Kamailio security” reveals https://www.cvedetails.com/vulnerability-list/vendor_id-15820/Kamailio.html as the most comprehensive source. However it lacks this latest header bug.
My suggestion would be to create a special “Security Advisories” page on the kamailio website which points to security news, so that Google indexes that page. As for example Asterisk has https://www.asterisk.org/downloads/security-advisories/ And create on github an extra “security” label so one can filter for that. https://github.com/kamailio/kamailio/labels And then point from the above mentioned “Security Advisories” page to a filtered github view. Thanks for your great work on Kamailio. Its highly appreciated! Best Gerry > On 22 Sep 2020, at 12:55, Daniel-Constantin Mierla <mico...@gmail.com> wrote: > > At least in my case you push out some inaccurate information. I never said my > "deployments were not affected since non-standard headers were not used". > > Iirc, I only said that none of my deployments were affected by this issue -- > respectively quoting from my message: "None of my deployments were affected." > from:https://lists.kamailio.org/pipermail/sr-users/2020-September/110315.html > <https://lists.kamailio.org/pipermail/sr-users/2020-September/110315.html> . > If I am mistaken and you found another remark from me, just point to my > message from where you got that. > > So, for further clarification: either non standard headers were used for > non-security related features (e.g., used for troubleshooting purposes) or > the issue didn't affect the deployments from different perspective (e.g., > traffic was checked to be from a trusted source). > > And remember that the issue was not with remove_hf() function itself, like it > is somehow propagated by blog posts, but it was in the parser, so use of > custom headers between two kamailio was not affected if an edge proxy did > something like: > > remove_hf("X-H"); > > append_hf("X-H: abc\r\n"); > > And then, if next hop Kamailio was using $hdr(X-H), it will get "abc" (value > added by previous Kamailio), not what a bad actor would add as "X-H : > badvalue\r\n" sip header. > > Then you listed two commits you consider there should have been security > advisories about. Have you analysed the code and found cases where security > was affected, or is just your opinion in based on the commit message and code > patch? > > First, I would love that one or many spend time to dissect commits and see > their security implication. I am more that happy when someone does it and > let's everyone be aware of, also to write and publish appropriate advisory. > > Otherwise, for those two specific commits you listed, the one from Federico > is a memory leak, I haven't spent time on going deeper to find the specific > cases, From header should be parsed in SIP requests. My commit was done based > on a static code analyzer and again I was not spending time to see what > implications are. > > In general, in the code we work a lot with str structure (non-zero terminated > char* and len), many of the "safety" commits done lately were to silent > static code analysers, not meaning that it was a real issue found behind. > Some can be, and here we appreciate the time and effort of people like you to > dissect them and make appropriate advisories. > > I would like people do verify what they write about what specific people (of > course, specially for my person) said before pushing out, and eventually > validate a commit to fix something has security impact, instead of just > personal guessing, if the intention is to help the project and not to create > more confusion or other reactions for what so ever reasons. > > This should be my last comment on the thread, I do not want to spend any more > time in clarifying what people think I said or I did. > > Cheers, > Daniel > > On 22.09.20 11:31, Sandro Gauci wrote: >> I know I am waking up an old debate by replying to this thread. Deeply sorry >> :-) >> >> Finally got around to writing up a blog post about this very thread where I >> (think) I spared absolutely no one, not even myself. >> >> My post is called "The great Kamailio security debate and some >> misconceptions debunked" and can be read here: >> >> https://www.rtcsec.com/2020/09/02-kamailio-security-debate-and-misconceptions/ >> >> <https://www.rtcsec.com/2020/09/02-kamailio-security-debate-and-misconceptions/> >> >> The ToC: >> Introduction >> A bit of background before diving in >> Claim: this issue does not affect many organisations >> Claim: custom headers are only known to internal users >> Claim: if it’s an 18 year old bug, it can’t have been high risk >> Claim: this should have been found if people were doing proper testing >> Claim: infrequent advisories = project is not serious about security >> Claim: limited number of advisories = project is more secure >> Claim: if you’re serious about security, monitor the mailing lists >> Claim: security experts should decide what is a security vulnerability >> Discussion: when should the project publish an advisory? >> Discussion: educational security role >> Moving forward >> Hope that it is at least interesting and perhaps even constructive! >> >> Best wishes, >> >> -- >> >> Sandro Gauci, CEO at Enable Security GmbH >> >> Register of Companies: AG Charlottenburg HRB 173016 B >> Company HQ: Pappelallee 78/79, 10437 Berlin, >> Germany >> PGP/Encrypted comms: https://keybase.io/sandrogauci >> <https://keybase.io/sandrogauci> >> Our blog: https://www.rtcsec.com >> <https://www.rtcsec.com/> >> Other points of contact: https://enablesecurity.com/#contact-us >> <https://enablesecurity.com/#contact-us> >> >> >> >> On Thu, 3 Sep 2020, at 10:34 AM, Olle E. Johansson wrote: >>> Well, you have defined one definitive line between being stupid and >>> following some current practise :-) >>> >>> I like to think we as a project have an educational role as well. In this >>> case explaining the bug we had and what it can cause. >>> We should definitely add a warning along the lines you write too - relying >>> on headers alone is bad and not best current practise. >>> >>> /O >>> >>>> On 3 Sep 2020, at 10:14, davy van de moere <davy.van.de.mo...@gmail.com >>>> <mailto:davy.van.de.mo...@gmail.com>> wrote: >>>> >>>> After 20 years in voip, my 2 cents on this, if you succeed in creating a >>>> voip system where the security of the whole relies on the ability to >>>> remove (or only keep specific) custom sip headers, you will wake up one >>>> morning realizing a bunch of people in Palestine made a gazillion calls >>>> over your system to expensive destinations, bringing you to or over the >>>> edge of bankruptcy. >>>> >>>> Security should be multilayered, one header sneaking through should not >>>> give any big problems. >>>> >>>> From a security point of view, this could be called a 'normal' security >>>> risk, I think. It's a bit more than low as you can do more than just get >>>> some info, but it's not high, as you would need to have many other factors >>>> going wrong to get to a successful exploit. >>>> >>>> >>>> >>>> >>>> Op do 3 sep. 2020 om 09:18 schreef Olle E. Johansson <o...@edvina.net >>>> <mailto:o...@edvina.net>>: >>>> One thought - we may have to separate security vulnerability reporting >>>> from security advisory documents. I think in some cases, where a common >>>> use of a product can lead to issues (but it is not clearly a bug that >>>> cause crashes in our code) we may have to send out an advisory and publish >>>> it in the same way. The problem with that is where the border is between >>>> just doing stupid things like taking SQL statements from SIP headers and >>>> issues like this that are harder to catch. >>>> >>>> We had a long and hard discussion about this in the Asterisk project many >>>> years ago - a very common dialplan construct (that was documented in many >>>> places) was indeed very dangerous. It wasn’t any code in asterisk that >>>> caused the issue, just a common dialplan construct that existed in many, >>>> many production systems. In the end, if I remember correctly, the project >>>> issued an advisory and added a README about it. >>>> >>>> Maybe that’s a way forward. >>>> >>>> /O >>>> >>>>> On 2 Sep 2020, at 21:25, Henning Westerholt <h...@skalatan.de >>>>> <mailto:h...@skalatan.de>> wrote: >>>>> >>>>> Hello Maxim, >>>>> >>>>> have a look to the first sentence: >>>>> >>>>> “A security vulnerability is (for example) when a user of Kamailio can >>>>> cause Kamailio to crash or lock up by sending messages to the server >>>>> process.” >>>>> >>>>> So there is some limitation regarding vulnerability criticality defined >>>>> in there. But of course (as I already mentioned), it might be improved to >>>>> e.g. use CVSS scoring instead. >>>>> >>>>> Cheers, >>>>> >>>>> Henning >>>>> >>>>> From: Maxim Sobolev <sobo...@sippysoft.com >>>>> <mailto:sobo...@sippysoft.com>> >>>>> Sent: Wednesday, September 2, 2020 9:15 PM >>>>> To: Henning Westerholt <h...@skalatan.de <mailto:h...@skalatan.de>> >>>>> Cc: Daniel-Constantin Mierla <mico...@gmail.com >>>>> <mailto:mico...@gmail.com>>; yufei....@gmail.com >>>>> <mailto:yufei....@gmail.com>; Olle E. Johansson <o...@edvina.net >>>>> <mailto:o...@edvina.net>>; Gerry | Rigatta <gjacob...@rigatta.com >>>>> <mailto:gjacob...@rigatta.com>>; Kamailio (SER) - Users Mailing List >>>>> <sr-users@lists.kamailio.org <mailto:sr-users@lists.kamailio.org>>; >>>>> jbro...@signalogic.com <mailto:jbro...@signalogic.com> >>>>> Subject: Re: [SR-Users] Kamailio vulnerable to header smuggling possible >>>>> due to bypass of remove_hf >>>>> >>>>> On Wed, Sep 2, 2020 at 11:30 AM Henning Westerholt <h...@skalatan.de >>>>> <mailto:h...@skalatan.de>> wrote: >>>>> Hello Maxim, >>>>> >>>>> thank you for the clarification, appreciated. >>>>> >>>>> No worries, hope to have a civilized discussion. >>>>> >>>>> Just one clarification, my comment regarding the advisory from 2018 was >>>>> not meant as advertisement etc.. >>>>> >>>>> Point taken, I dramatized of course to underline my point. >>>>> >>>>> One suggestion to objectify the whole discussion, there exists a >>>>> well-known and accepted metric for vulnerabilities: CVSS [1] >>>>> If I calculate the CVSS score for this issue, it results in a medium >>>>> level with score 5.8. But this is of course again (at least somewhat) >>>>> influenced from my point of view to this bug. >>>>> >>>>> Some projects have a policy to only do a security announcement for >>>>> vulnerabilities with score high and critical. For Kamailio this is not >>>>> yet defined in a detailed way, due to the size of the project and other >>>>> factors. >>>>> >>>>> So, If people in this discussion (or other people on the list) are >>>>> interested in improving the project security processes – this wiki page >>>>> with the current process might be a good starting >>>>> point:https://www.kamailio.org/wiki/security/policy >>>>> <https://www.kamailio.org/wiki/security/policy> >>>>> >>>>> Please suggest your improvements to the existing process (preferable in a >>>>> new discussion thread) on the sr-dev list. If you want to do it in >>>>> private, feel free contact the management list. >>>>> >>>>> Well, first suggestion after having read it: to start actually following >>>>> what's documented before any improvements are made. ;-) The policy says >>>>> plain and simple (quote): >>>>> >>>>> Publishing security vulnerabilities >>>>> >>>>> Kamailio will publish security vulnerabilities, including an CVE ID, on >>>>> the kamailio-business mailing list, sr-dev, sr-users as well as related >>>>> lists. The advisories will also be published on the kamailio.org >>>>> <http://kamailio.org/> web site. >>>>> >>>>> CVE entries should be created for vulnerabilities in the core and major >>>>> modules, for rarely used modules this is not necessary. If there are >>>>> several security issues together in one release, they should be announced >>>>> together. >>>>> >>>>> I might be missing something obvious, but there is no "if" or "maybe" or >>>>> "it depends". Any module that has been 18 years with the project >>>>> qualifies to be a "major module" to me... >>>>> >>>>> -Max >>>> >>>> >>>> _______________________________________________ >>>> Kamailio (SER) - Users Mailing List >>>> sr-users@lists.kamailio.org <mailto:sr-users@lists.kamailio.org> >>>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>>> <https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users> >>>> _______________________________________________ >>>> Kamailio (SER) - Users Mailing List >>>> sr-users@lists.kamailio.org <mailto:sr-users@lists.kamailio.org> >>>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>>> <https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users> >>> >>> _______________________________________________ >>> Kamailio (SER) - Users Mailing List >>> sr-users@lists.kamailio.org <mailto:sr-users@lists.kamailio.org> >>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>> <https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users> >>> >> >> >> >> _______________________________________________ >> Kamailio (SER) - Users Mailing List >> sr-users@lists.kamailio.org <mailto:sr-users@lists.kamailio.org> >> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >> <https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users> > -- > Daniel-Constantin Mierla -- www.asipto.com <http://www.asipto.com/> > www.twitter.com/miconda <http://www.twitter.com/miconda> -- > www.linkedin.com/in/miconda <http://www.linkedin.com/in/miconda> > Funding: https://www.paypal.me/dcmierla > <https://www.paypal.me/dcmierla>_______________________________________________ > Kamailio (SER) - Users Mailing List > sr-users@lists.kamailio.org <mailto:sr-users@lists.kamailio.org> > https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users > <https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users>
_______________________________________________ Kamailio (SER) - Users Mailing List sr-users@lists.kamailio.org https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users
