==================================================================== CERT-Renater Note d'Information No. 2012/VULN292 ____________________________________________________________________ DATE : 25/07/2012 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S) : Systems running ISC DHCP versions prior to 4.1-ESV-R6, 4.2.4-P1. ====================================================================== https://lists.isc.org/pipermail/dhcp-announce/2012-July/000341.html https://lists.isc.org/pipermail/dhcp-announce/2012-July/000343.html https://lists.isc.org/pipermail/dhcp-announce/2012-July/000342.html ______________________________________________________________________ Note: This email advisory is provided for your information. The most up to date advisory information will always be at: https://kb.isc.org/article/AA-00712 please use this URL for the most up to date advisory information. Title: An error in the handling of malformed client identifiers can cause a denial-of-service condition in affected servers. CVE: CVE-2012-3571 Document Version: 2.0 Posting date: 24 Jul 2012 Program Impacted: DHCP Versions affected: All versions of 4.2 (including 4.2.x-Px) to 4.2.4; 4.1-ESV through 4.1-ESV-R5; 4.1.2, 4.1.2-P1 Severity: High Exploitable: Locally - From adjacent networks Description: An error in the handling of malformed client identifiers can cause a DHCP server running affected versions (see "Impact") to enter a state where further client requests are not processed and the server process loops endlessly, consuming all available CPU cycles. Under normal circumstances this condition should not be triggered, but a non-conforming or malicious client could deliberately trigger it in a vulnerable server. In order to exploit this condition an attacker must be able to send requests to the DHCP server . Impact: Causes the server process to loop endlessly, resulting in a denial of service. NOTE: ISC DHCP 3.0.x and ISC DHCP 4.0.x are EOL and have not been tested for this vulnerability. Versions of ISC DHCP that are vulnerable to CVE-2010-2156 (including 4.1.0 through 4.1.1-P1) can be expected to terminate unexpectedly instead of looping endlessly. CVSS Score: 6.1 CVSS Equation: (AV:A/AC:L/Au:N/C:N/I:N/A:C) For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2&vector=(AV:A/AC:L/Au:N/C:N/I:N/A:C) Workarounds: None. Active exploits: None known at this time. Solution: Upgrade affected systems to DHCP 4.1-ESV-R6 or DHCP 4.2.4-P1 DHCP 4.2.4-P1 is available from www.isc.org/downloads/all DHCP 4.1-ESV-R6 is available from www.isc.org/downloads/all Acknowledgment: Markus Hietava of Codenomicon CROSS project for finding the vulnerability, and CERT-FI for vulnerability coordination. Document Revision History: 1.0 - 03 July 2012 Phase I notified 1.1 - 13 July 2012 HOLD notice sent to Phase 1 regarding new CVE being added and new public release date 1.2 - 23 July 2012 Phase 2 & 3 notified 2.0 - 24 July 2012 Phase 4-Public released References: Do you have Questions? Questions regarding this advisory should go to security-officer at isc.org. ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found here: https://www.isc.org/security-vulnerability-disclosure-policy German Translation: https://kb.isc.org/article/AA-00739 Spanish Translation: https://kb.isc.org/article/AA-00747 Japanese Translation: https://kb.isc.org/article/AA-00755 Legal Disclaimer: Internet Systems Consortium (ISC) is providing this notice on an "AS IS" basis. No warranty or guarantee of any kind is expressed in this notice and none should be implied. ISC expressly excludes and disclaims any warranties regarding this notice or materials referred to in this notice, including, without limitation, any implied warranty of merchantability, fitness for a particular purpose, absence of hidden defects, or of non-infringement. Your use or reliance on this notice or materials referred to in this notice is at your own risk. ISC may change this notice at any time. A stand-alone copy or paraphrase of the text of this document that omits the document URL is an uncontrolled copy. Uncontrolled copies may lack important information, be out of date, or contain factual errors. ______________________________________________________________________ Note: This email advisory is provided for your information. The most up to date advisory information will always be at: https://kb.isc.org/article/AA-00714 please use this URL for the most up to date advisory information. Title: An error in the handling of an unexpected client identifiers can cause a server crash when serving DHCPv6. CVE: CVE-2012-3570 Document Version: 2.0 Posting date: 24 Jul 2012 Program Impacted: DHCP Versions affected: 4.2.0 --> 4.2.4 Severity: High Exploitable: From adjacent networks Description: An unexpected client identifier parameter can cause the ISC DHCP daemon to segmentation fault when running in DHCPv6 mode, resulting in a denial of service to further client requests. In order to exploit this condition, an attacker must be able to send requests to the DHCP server. Impact: Causes the server process to crash when a buffer overflows, resulting in a denial of service. NOTE: DHCP versions 4.0 -->4.1.x are NOT impacted. CVSS Score: 6.1 CVSS Equation: (AV:A/AC:L/Au:N/C:N/I:N/A:C) For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2&vector=(AV:A/AC:L/Au:N/C:N/I:N/A:C) Workarounds: None. Active exploits: None known at this time. Solution: Upgrade affected systems to DHCP 4.2.4-P1 DHCP 4.2.4-P1 is available from www.isc.org/downloads/all Acknowledgment: Markus Hietava of Codenomicon CROSS project for finding the vulnerability, and CERT-FI for vulnerability coordination. Document Revision History: 1.0 - 03 July 2012 - Phase I notified 1.1 - 13 July 2012 HOLD notice sent to Phase 1 regarding new CVE being added and new public release date 1.2 - 23 July 2012 Phase 2 & 3 notified 2.0 - 24 July 2012 Phase 4-Public release References: Do you have Questions? Questions regarding this advisory should go to security-officer at isc.org. ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found here: https://www.isc.org/security-vulnerability-disclosure-policy German Translation: https://kb.isc.org/article/AA-00740 Spanish Translation: https://kb.isc.org/article/AA-00745 Japanese Translation: https://kb.isc.org/article/AA-00756 This security advisory is also located in our KnowledgeBase: https://kb.isc.org/Article/AA-00714 Note: ISC patches only Currently supported versions. When possible we indicate EOL versions affected. If you'd like more information on our Forum or BIND/DHCP support please visit www.isc.org/software/guild or www.isc.org/support Legal Disclaimer: Internet Systems Consortium (ISC) is providing this notice on an "AS IS" basis. No warranty or guarantee of any kind is expressed in this notice and none should be implied. ISC expressly excludes and disclaims any warranties regarding this notice or materials referred to in this notice, including, without limitation, any implied warranty of merchantability, fitness for a particular purpose, absence of hidden defects, or of non-infringement. Your use or reliance on this notice or materials referred to in this notice is at your own risk. ISC may change this notice at any time. A stand-alone copy or paraphrase of the text of this document that omits the document URL is an uncontrolled copy. Uncontrolled copies may lack important information, be out of date, or contain factual errors. ______________________________________________________________________ Note: This email advisory is provided for your information. The most up to date advisory information will always be at: https://kb.isc.org/article/AA-00737 please use this URL for the most up to date advisory information. Title: Memory Leaks Found In ISC DHCP Summary: Two memory leaks have been found and fixed in ISC DHCP. Both are reproducible when running in DHCPv6 mode (with the -6 command-line argument.) The first leak is confirmed to only affect servers operating in DHCPv6 mode, but based on initial code analysis the second may theoretically affect DHCPv4 servers (though this has not been demonstrated.) CVE: CVE-2012-3954 Document Version: 2.0 Posting date: 24 July 2012 Program Impacted: ISC DHCP 4 Versions affected: 4.1.x, 4.2.x Severity: Medium Exploitable: From networks permitted to send requests to the DHCP server. Description: ISC has discovered and fixed two memory leaks in the DHCP code. One of the leaks only affects servers running in DHCPv6 mode. The other is known to affect a server running in DHCPv6 mode but could potentially occur on servers running in DHCPv4 mode as well. In both cases the server can leak a small amount of memory while processing messages. The amount leaked per iteration is small and the leak will not cause problems in many cases. However on a server that is run for a long period without re-starting or a server handling an extraordinary amount of traffic from the clients the leak could consume all memory available to the DHCP server process, preventing further operation by the DHCP server process and potentially interfering with other services hosted on the same server hardware. Note: Under ISC's disclosure policy, this issue would not normally require an advisory but we are issuing one in this case in coordination with other security issues being disclosed at this time. DHCP 3.1-ESV has not been tested for this issue but examination of the code suggests that it is potentially vulnerable. All versions of ISC DHCP 3 are currently beyond the end of their support from ISC and we will not be releasing patches for these "End of Life" (EOL) versions. CVSS Score: 3.3 CVSS Equation: (AV:A/AC:L/Au:N/C:N/I:N/A:P) For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit:http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2&vector=(AV:A/AC:L/Au:N/C:N/I:N/A:P) Workarounds: Restarting the server at periodic intervals will address the problem sufficiently in most operational environments. Where DHCP traffic is permitted from hosts not under the control of the network operator (e.g. open or semi-public networks) upgrading is more strongly recommended. Solution: Upgrade to ISC DHCP 4.1-ESV-R6 or 4.2.4-P1 Download 4.2.4-P1 or 4.1-ESV-R6 from www.isc.org/downloads/all Exploit Status: No known active exploits Acknowledgment: ISC would like to thank Glen Eustace of Massey University, New Zealand for finding this issue. Document Revision History: 1.0 - 11 July, 2012 - Phase 1 contacted 1.1 - 17 July, 2012. - Phase 1 re-issued, re-released patch with additional code 1.2 - 23 July, 2012 - Phase 2 & 3 notification sent 2.0 - 24 July, 2012 - Phase 4-Public release References: - Do you have Questions? Questions regarding this advisory should go to security-officer at isc.org. - ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found here:https://www.isc.org/security-vulnerability-disclosure-policy - Japanese Translation: https://kb.isc.org/article/AA-00754 - Spanish Translation: https://kb.isc.org/article/AA-00749 - German Translation: https://kb.isc.org/article/AA-00738 If you'd like more information on our Forum or BIND/DHCP support please visit www.isc.org/software/guild or www.isc.org/support Legal Disclaimer: Internet Systems Consortium (ISC) is providing this notice on an "AS IS" basis. No warranty or guarantee of any kind is expressed in this notice and none should be inferred. ISC expressly excludes and disclaims any warranties regarding this notice or materials referred to in this notice, including, without limitation, any inferred warranty of merchantability, fitness for a particular purpose, absence of hidden defects, or of non-infringement. Your use of, or reliance on, this notice or materials referred to in this notice is at your own risk. ISC may change this notice at any time. A stand-alone copy or paraphrase of the text of this document that omits the distribution URL in the following section is an uncontrolled copy. Uncontrolled copies may lack important information, be out of date, or contain factual errors. ====================================================================== ========================================================= Serveur de référence du CERT-Renater https://services.renater.fr/ssi/ ========================================================= + CERT-RENATER | tel : 01-53-94-20-44 + + 23 - 25 Rue Daviel | fax : 01-53-94-20-41 + + 75013 Paris | email: certsvp@renater.fr + =========================================================