INTERNET-DRAFT Steven M. Bellovin draft-ymbk-obscurity-00.txt Randy Bush 2002.02.28 AT&T Research Security Through Obscurity Considered Dangerous Copyright (C) The Internet Society (2002). All Rights Reserved. This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. 0. Abstract Hiding security vulnerabilities in algorithms, software, and/or hardware decreases the likelihood they will be repaired and increases the likelihood that they can and will be exploited by evil-doers. Discouraging or outlawing discussion of weaknesses and vulnerabilities is extremely dangerous and deleterious to the security of computer systems, the network, and its citizens. 1. Open Discussion Encourages Better Security The long history of cryptography and cryptoanalysis has shown time and time again that open discussion and analysis of algorithms exposes weaknesses not thought of by the original authors, and thereby leads to better and more secure algorithms. As Kerckhoff noted about cipher systems in 1883 [Kerc83], "Il faut qu'il n'exige pas le secret, et qu'il puisse sans inconv'enient tomer entre les mains de l'ennemi." (Roughly, "the system must not require secrecy and can be stolen by the enemy without causing trouble.") Bellovin & Bush Expires 2002.08.28 [Page 1]
INTERNET-DRAFT Security Through Obscurity Dangerous 2002.02.28 It is also against the ethos and laws of a number of countries to disallow open discussion of science and technology. Within the IETF, frank discussion of the flaws of proposed and actual protocols has led to improvement versions. Hence, the IETF does not discourage open discussion and analysis of cryptographic or security methods, and enthusiastically encourages open and frank technical discussion thereof in its research, working groups, mailing lists, and all other discussion venues. 2. Revealing Vulnerabilities is Useful Revealing and discussing vulnerabilities in hardware and software products allows the users to protect themselves, and encourages general protection and repair strategies. On the other hand, there is a well-established culture of giving the manufacturer of the vulnerable product a short but reasonable early warning of discovered vulnerabilities so that they have an opportunity to repair them and or prepare to distribute patches or work-arounds. Furthermore, it is better if developers have time to test their patches; much of the current mess comes from inadequate software testing. The IETF supports and encourages the open but prudent discussion of vulnerabilities in hardware and software in all appropriate IETF venues. 3. The Culture of Sharing In parts of the hacker subculture, information is currency. That is, by disclosing vulnerabilities or by providing exploit code, the purveyor gains status. As a consequence, knowledge of security holes tends to spread rapidly. By contrast, when security professionals withhold such information from the community, the broader community does not have an opportunity to find solutions. In extreme cases, such as that described in [Bell95], the result can be that the bad guys know about the problem long before most defenders do. That, in turn, likely delayed the development of cryptographic security mechanisms for the DNS [RFC2065]. Bellovin & Bush Expires 2002.08.28 [Page 2]
INTERNET-DRAFT Security Through Obscurity Dangerous 2002.02.28 3. Security Considerations This document is about security, and specifically warns about increased vulnerability if weakness in algorithms and products are not able to be openly discussed. 4. Acknowledgments I dunno 5. References [Bell95] S..M. Bellovin, "Using the Domain Name System for System Break- Ins", Proc. Fifth Usenix Security Symposium, 1995. [Kerc83] A. Kerckhoffs. "La Cryptographie Militaire". 1883. <http://www.cl.cam.ac.uk/~fapp2/kerckhoffs/> [RFC2065] D. Eastlake and C. Kaufman. "Domain Name System Security Exten- sions". RFC 2065, 1997. 6. Authors' Addresses Steven M Bellovin AT&T Labs Research Shannon Laboratory 180 Park Avenue Florham Park, NJ 07932 Phone: +1 973-360-8656 email: bellovin@acm.org Randy Bush 5147 Crystal Springs Bainbridge Island, WA US-98110 +1 206 780 0431 randy@psg.com Bellovin & Bush Expires 2002.08.28 [Page 3]
INTERNET-DRAFT Security Through Obscurity Dangerous 2002.02.28 7. Full Copyright Statement Copyright (C) The Internet Society (2001). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of develop- ing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Bellovin & Bush Expires 2002.08.28 [Page 4]