--- title: "CVE-2012-3570: An Error in the Handling of an Unexpected Client" slug: "aa-00714" description: "CVE-2012-3570: An Error in the Handling of an Unexpected Client Identifiers can Cause Server Crash When Serving DHCPv6" tags: ["isc dhcp"] updated: 2025-03-24T21:55:51Z published: 2025-03-24T21:55:51Z --- > ## Documentation Index > Fetch the complete documentation index at: https://kb.isc.org/llms.txt > Use this file to discover all available pages before exploring further. # CVE-2012-3570: An Error in the Handling of an Unexpected Client Identifiers can Cause Server Crash When Serving DHCPv6 **Title:** An error in the handling of an unexpected client identifiers can cause a server crash when serving DHCPv6. CVE: [CVE-2012-3570](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-3570) Document Version: 2.2 Posting date: 24 Jul 2012 Program Impacted: [DHCP](https://www.isc.org/software/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)](http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2&vector=%28AV:A/AC:L/Au:N/C:N/I:N/A:C%29) **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](http://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 2.1 - 30 July 2012 Added Chinese Translation 2.2 - 4 August 2021 Updated broken links **References** : - Do you have Questions? Questions regarding this advisory should go to [security-officer@isc.org](mailto:security-officer@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](https://www.isc.org/security-vulnerability-disclosure-policy) - German Translation:  [https://kb.isc.org/docs/aa-00740](https://kb.isc.org/docs/aa-00740) - Spanish Translation:  [https://kb.isc.org/docs/aa-00745](https://kb.isc.org/docs/aa-00745) - Japanese Translation: [https://kb.isc.org/docs/aa-00756](https://kb.isc.org/docs/aa-00756) - Chinese Translation:  [https://kb.isc.org/docs/aa-00761](https://kb.isc.org/docs/aa-00761) This security advisory is also located in our [KnowledgeBase](https://kb.isc.org/docs): https://kb.isc.org/docs/aa-00714 Note: ISC patches only [Currently supported versions](http://www.isc.org/software/dhcp/versions). When possible we indicate EOL versions affected. 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