=================================================================== CERT-Renater Note d'Information No. 2023/VULN028 _____________________________________________________________________ DATE : 26/01/2023 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Systems running Bind versions prior to 9.16.37, 9.18.11, 9.19.9, 9.16.37-S1. ====================================================================https://kb.isc.org/docs/cve-2022-3094 https://kb.isc.org/docs/cve-2022-3924 https://kb.isc.org/docs/cve-2022-3736 _____________________________________________________________________ CVE-2022-3094: An UPDATE message flood may cause named to exhaust all available memory Updated on 25 Jan 2023 Contributors [Cathy Almond] [Peter Davies] CVE: CVE-2022-3094 Document version: 2.1 Posting date: 25 January 2023 Program impacted: BIND 9 Versions affected: BIND 9.16.0 -> 9.16.36 9.18.0 -> 9.18.10 9.19.0 -> 9.19.8 (Versions prior to 9.11.37 were not assessed.) BIND Supported Preview Edition 9.16.8-S1 -> 9.16.36-S1 (Versions prior to 9.11.37-S1 were not assessed.) Severity: High Exploitable: Remotely Description: Sending a flood of dynamic DNS updates may cause named to allocate large amounts of memory. This, in turn, may cause named to exit due to a lack of free memory. We are not aware of any cases where this has been exploited. Memory is allocated prior to the checking of access permissions (ACLs) and is retained during the processing of a dynamic update from a client whose access credentials are accepted. Memory allocated to clients that are not permitted to send updates is released immediately upon rejection. The scope of this vulnerability is limited therefore to trusted clients who are permitted to make dynamic zone changes. If a dynamic update is REFUSED, memory will be released again very quickly. Therefore it is only likely to be possible to degrade or stop named by sending a flood of unaccepted dynamic updates comparable in magnitude to a query flood intended to achieve the same detrimental outcome. BIND 9.11 and earlier branches are also affected, but through exhaustion of internal resources rather than memory constraints. This may reduce performance but should not be a significant problem for most servers. Therefore we don't intend to address this for BIND versions prior to BIND 9.16. Impact: By flooding the target server with UPDATE requests, the attacker can exhaust all available memory on that server. CVSS Score: 7.5 CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit: https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H&version=3.1. Workarounds: No workarounds known. Active exploits: We are not aware of any active exploits. Solution: Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.37 9.18.11 9.19.9 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. 9.16.37-S1 Acknowledgments: ISC would like to thank Rob Schulhof from Infoblox for bringing this vulnerability to our attention. Document revision history: 1.0 Early Notification, 18 January 2023 2.0 Public disclosure, 25 January 2023 2.1 Correction to BIND Supported Preview Edition affected versions, 25 January 2023 Related documents: See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected. Do you still have questions? Questions regarding this advisory should be mailed to security-officer@isc.org. To report a new issue, please encrypt your message using security-officer@isc.org's PGP key, which can be found here: https://www.isc.org/pgpkey/. If you are unable to use encrypted email you may also report new issues at: https://www.isc.org/reportbug/. Note: ISC patches only currently supported versions. When possible we indicate EOL versions affected. For current information on which versions are actively supported, please see https://www.isc.org/download/. ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found in the ISC Software Defect and Security Vulnerability Disclosure Policy at https://kb.isc.org/docs/aa-00861. The Knowledgebase article https://kb.isc.org/docs/cve-2022-3094 is the complete and official security advisory document. 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. _____________________________________________________________________ CVE-2022-3924: named configured to answer from stale cache may terminate unexpectedly at recursive-clients soft quota Updated on 25 Jan 2023 Contributors [Cathy Almond] [Peter Davies] [Matthijs Mekking] CVE: CVE-2022-3924 Document version: 2.0 Posting date: 25 January 2023 Program impacted: BIND 9 Versions affected: BIND 9.16.12 -> 9.16.36 9.18.0 -> 9.18.10 9.19.0 -> 9.19.8 BIND Supported Preview Edition 9.16.12-S1 -> 9.16.36-S1 (The flaw exists in the implementation of the stale-answer-client-timeout option, which was first effectively introduced in BIND 9.16.12 and BIND 9.16.12-S1. That option is also configurable in BIND 9.11.33-S1 and newer BIND 9.11-S versions, but it is always replaced with 0 in all BIND 9.11.x-S1 releases.) Severity: High Exploitable: Remotely Description: This issue can affect BIND 9 resolvers with stale-answer-enable yes; that also make use of the option stale-answer-client-timeout, configured with a value greater than zero. If the resolver receives many queries that require recursion, there will be a corresponding increase in the number of clients that are waiting for recursion to complete. If there are sufficient clients already waiting when a new client query is received so that it is necessary to SERVFAIL the longest waiting client (see BIND 9 ARM recursive-clients limit and soft quota), then it is possible for a race to occur between providing a stale answer to this older client and sending an early timeout SERVFAIL, which may cause an assertion failure. Impact: By sending specific queries to the resolver, an attacker can cause named to crash. CVSS Score: 7.5 CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit: https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H&version=3.1. Workarounds: Disabling stale-answer-client-timeout entirely or setting the timeout value to zero prevents the problem. It is not possible to disable the limit on recursive-clients, though it could be set to a very high value in order to reduce the likelihood of encountering this scenario. However, this is not recommended as the limit on recursive clients is important for preventing exhaustion of server resources. Active exploits: We are not aware of any active exploits. Solution: Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.37 9.18.11 9.19.9 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. 9.16.37-S1 Acknowledgments: ISC would like to thank Maksym Odinintsev from AWS for bringing this vulnerability to our attention. Document revision history: 1.0 Early Notification, 18 January 2023 2.0 Public disclosure, 25 January 2023 Related documents: See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected. Do you still have questions? Questions regarding this advisory should be mailed to security-officer@isc.org. To report a new issue, please encrypt your message using security-officer@isc.org's PGP key, which can be found here: https://www.isc.org/pgpkey/. If you are unable to use encrypted email you may also report new issues at: https://www.isc.org/reportbug/. Note: ISC patches only currently supported versions. When possible we indicate EOL versions affected. For current information on which versions are actively supported, please see https://www.isc.org/download/. ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found in the ISC Software Defect and Security Vulnerability Disclosure Policy at https://kb.isc.org/docs/aa-00861. The Knowledgebase article https://kb.isc.org/docs/cve-2022-3924 is the complete and official security advisory document. 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. _____________________________________________________________________ CVE-2022-3736: named configured to answer from stale cache may terminate unexpectedly while processing RRSIG queries Updated on 25 Jan 2023 Contributors [Cathy Almond] CVE: CVE-2022-3736 Document version: 2.0 Posting date: 25 January 2023 Program impacted: BIND 9 Versions affected: BIND 9.16.12 -> 9.16.36 9.18.0 -> 9.18.10 9.19.0 -> 9.19.8 BIND Supported Preview Edition 9.16.12-S1 -> 9.16.36-S1 (The flaw exists in the implementation of the stale-answer-client-timeout option, which was first effectively introduced in BIND 9.16.12 and BIND 9.16.12-S1. That option is also configurable in BIND 9.11.33-S1 and newer BIND 9.11-S versions, but it is always replaced with 0 in all BIND 9.11.x-S1 releases.) Severity: High Exploitable: Remotely Description: BIND 9 resolver can crash when stale cache and stale answers are enabled, option stale-answer-client-timeout is set to a positive integer, and the resolver receives an RRSIG query. Impact: By sending specific queries to the resolver, an attacker can cause named to crash. CVSS Score: 7.5 CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit: https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H&version=3.1. Workarounds: Setting stale-answer-client-timeout to 0 or to off/disabled will prevent BIND from crashing due to this issue. Active exploits: We are not aware of any active exploits. Solution: Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.37 9.18.11 9.19.9 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. 9.16.37-S1 Acknowledgments: ISC would like to thank Borja Marcos from Sarenet (with assistance by Iratxe Niño from Fundación Sarenet) for bringing this vulnerability to our attention. Document revision history: 1.0 Early Notification, 18 January 2023 2.0 Public disclosure, 25 January 2023 Related documents: See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected. Do you still have questions? Questions regarding this advisory should be mailed to security-officer@isc.org. To report a new issue, please encrypt your message using security-officer@isc.org's PGP key, which can be found here: https://www.isc.org/pgpkey/. If you are unable to use encrypted email you may also report new issues at: https://www.isc.org/reportbug/. Note: ISC patches only currently supported versions. When possible we indicate EOL versions affected. For current information on which versions are actively supported, please see https://www.isc.org/download/. ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found in the ISC Software Defect and Security Vulnerability Disclosure Policy at https://kb.isc.org/docs/aa-00861. The Knowledgebase article https://kb.isc.org/docs/cve-2022-3736 is the complete and official security advisory document. 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. ========================================================+ CERT-RENATER | tel : 01-53-94-20-44 + + 23/25 Rue Daviel | fax : 01-53-94-20-41 + + 75013 Paris | email:cert@support.renater.fr + =======================================================