Ce mail provient de l'extérieur, restons vigilants ===================================================================== CERT-Renater Note d'Information No. 2026/VULN523 _____________________________________________________________________ DATE : 20/05/2026 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Systems running BIND versions prior to 9.18.49, 9.20.23, 9.21.22, 9.18.49-S1, 9.20.23-S1. ===================================================================== https://kb.isc.org/docs/cve-2026-3039 https://kb.isc.org/docs/cve-2026-3592 https://kb.isc.org/docs/cve-2026-3593 _____________________________________________________________________ CVE-2026-3039: BIND 9 server memory exhaustion during GSS-API TKEY negotiation CVE: CVE-2026-3039 Title: BIND 9 server memory exhaustion during GSS-API TKEY negotiation Document version: 2.0 Posting date: 20 May 2026 Program impacted: BIND 9 Versions affected: BIND 9.0.0 -> 9.16.50 9.18.0 -> 9.18.48 9.20.0 -> 9.20.22 9.21.0 -> 9.21.21 BIND Supported Preview Edition 9.9.3-S1 -> 9.16.50-S1 9.18.11-S1 -> 9.18.48-S1 9.20.9-S1 -> 9.20.22-S1 (Versions prior to 9.11.37 were not assessed.) Although we have not tested them individually, we believe that all EoL versions of BIND are vulnerable to this weakness. Severity: High Exploitable: Remotely Description: BIND servers that are configured to use TKEY-based authentication via GSS-API tokens are vulnerable to excessive memory consumption when receiving and processing maliciously-constructed packets. Typically these servers will be found in Active Directory integrated DNS deployments and/or Kerberos-secured DNS environments. Impact: An attacker can construct and send packets to a BIND server that will cause it to allocate memory that is not subsequently released. Depending on the volume and frequency of the packets received, named will eventually fail due to memory exhaustion. 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: 9.18.49 9.20.23 9.21.22 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. 9.18.49-S1 9.20.23-S1 Acknowledgments: ISC would like to thank Vitaly Simonovich for bringing this vulnerability to our attention. Document revision history: 1.0 Early Notification, 13 May 2026 1.1 Remove references to keytab (using GSS-API TKEY is sufficient for exposure), 14 May 2026 2.0 Public disclosure, 20 May 2026 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 bind-security@isc.org or posted as confidential GitLab issues at https://gitlab.isc.org/isc-projects/bind9/-/issues/new?issue[confidential]=true. 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-2026-3039 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: CVE-2026-3592 Title: Amplification vulnerabilities via self-pointed glue records Document version: 2.0 Posting date: 20 May 2026 Program impacted: BIND 9 Versions affected: BIND 9.11.0 -> 9.16.50 9.18.0 -> 9.18.48 9.20.0 -> 9.20.22 9.21.0 -> 9.21.21 BIND Supported Preview Edition 9.11.3-S1 -> 9.16.50-S1 9.18.11-S1 -> 9.18.48-S1 9.20.9-S1 -> 9.20.22-S1 Severity: Medium Exploitable: Remotely Description: BIND resolvers are vulnerable to an amplified resource consumption/exhaustion attack. If a victim resolver makes a query to a specially crafted zone, the resolver will consume disproportionate resources. Impact: An attacker may be able to cause the resolver to consume disproportionate amounts of bandwidth in the attempt to resolve the name. Impairment of TCP may also be seen. The issue predominately affects recursive resolvers. Authoritative-only servers containing only trustworthy zones and names should be unaffected. If an authoritative server can be induced to look up an attack domain (e.g., if loading a zone from an untrusted source), it may be possible to trigger the issue. Authoritative services are believed to be unaffected by this vulnerability but it is important to read: https://kb.isc.org/docs/why-does-my-authoritative-server-make-recursive-queries Resolvers are affected by this vulnerability. CVSS Score: 5.3 CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L 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:L&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: 9.18.49 9.20.23 9.21.22 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. 9.18.49-S1 9.20.23-S1 Acknowledgments: ISC would like to thank Shuhan Zhang from Tsinghua University for bringing this vulnerability to our attention. Document revision history: 1.0 Early Notification, 13 May 2026 2.0 Public disclosure, 20 May 2026 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 bind-security@isc.org or posted as confidential GitLab issues at https://gitlab.isc.org/isc-projects/bind9/-/issues/new?issue[confidential]=true. 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-2026-3592 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: CVE-2026-3593 Title: Heap use-after-free vulnerability in BIND 9 DNS-over-HTTPS implementation Document version: 2.0 Posting date: 20 May 2026 Program impacted: BIND 9 Versions affected: BIND 9.20.0 -> 9.20.22 9.21.0 -> 9.21.21 BIND Supported Preview Edition 9.20.9-S1 -> 9.20.22-S1 Versions NOT affected: BIND 9.18.0 -> 9.18.48 BIND Supported Preview Edition 9.18.11-S1 -> 9.18.48-S1 (Versions prior to 9.18.0 and 9.18.11-S1 were not assessed.) Severity: High Exploitable: Remotely Description: A use-after-free vulnerability exists within the DNS-over-HTTPS implementation. Impact: Crafted HTTP/2 traffic sent to a DNS-over-HTTPS endpoint can be used to trigger memory corruption. Authoritative servers are affected by this vulnerability. Resolvers are affected by this vulnerability. CVSS Score: 7.4 CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/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:H/PR:N/UI:N/S:U/C:H/I:N/A:H&version=3.1. Workarounds: Configurations not using DNS-over-HTTPS should not be affected. Disabling DNS-over-HTTPS is likewise an effective workaround. 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: 9.20.23 9.21.22 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. 9.20.23-S1 Acknowledgments: ISC would like to thank Naresh Kandula Parmar (Nottiboy) for bringing this vulnerability to our attention. Document revision history: 1.0 Early Notification, 13 May 2026 2.0 Public disclosure, 20 May 2026 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 bind-security@isc.org or posted as confidential GitLab issues at https://gitlab.isc.org/isc-projects/bind9/-/issues/new?issue[confidential]=true. 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-2026-3593 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 + =========================================================