Vulnerability · Published Feb 13, 2024 · Assigned by isc
CVE-2023-6516Specific recursive query patterns may lead to an out-of-memory condition
High 7.5
In plain English
A high-severity security flaw in BIND 9 from ISC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 66% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
To keep its cache database efficient, `named` running as a recursive resolver occasionally attempts to clean up the database. It uses several methods, including some that are asynchronous: a small chunk of memory pointing to the cache element that can be cleaned up is first allocated and then queued for later processing. It was discovered that if the resolver is continuously processing query patterns triggering this type of cache-database maintenance, `named` may not be able to handle the cleanup events in a timely manner. This in turn enables the list of queued cleanup events to grow infinitely large over time, allowing the configured `max-cache-size` limit to be significantly exceeded. This issue affects BIND 9 versions 9.16.0 through 9.16.45 and 9.16.8-S1 through 9.16.45-S1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:9 | bind | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-chroot | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-chroot | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-devel | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-devel | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-dnssec-doc | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-dnssec-doc | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-dnssec-utils | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-dnssec-utils | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-doc | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-doc | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-dyndb-ldap | 11.9-9.el9_4.alma.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-dyndb-ldap | 11.9-8.el9_3.3.alma.1 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-libs | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-libs | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-license | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | bind-license | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-utils | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:9 | bind-utils | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:8 | bind9.16 | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| AlmaLinux:8 | bind9.16-chroot | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| AlmaLinux:8 | bind9.16-devel | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| AlmaLinux:8 | bind9.16-dnssec-utils | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| AlmaLinux:8 | bind9.16-doc | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| AlmaLinux:8 | bind9.16-libs | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| AlmaLinux:8 | bind9.16-license | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| AlmaLinux:8 | bind9.16-utils | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| AlmaLinux:9 | python3-bind | 32:9.16.23-18.el9_4.1 | ALSA-2024:2551 |
| AlmaLinux:9 | python3-bind | 32:9.16.23-14.el9_3.4 | ALSA-2024:1789 |
| AlmaLinux:8 | python3-bind9.16 | 32:9.16.23-0.16.el8_9.2.alma.1 | ALSA-2024:1781 |
| Alpine:v3.20 | bind | 9.18.24-r0 | ALPINE-CVE-2023-6516 |
| Alpine:v3.21 | bind | 9.18.24-r0 | ALPINE-CVE-2023-6516 |
| Alpine:v3.22 | bind | 9.18.24-r0 | ALPINE-CVE-2023-6516 |
| Alpine:v3.23 | bind | 9.18.24-r0 | ALPINE-CVE-2023-6516 |
| Alpine:v3.24 | bind | 9.18.24-r0 | ALPINE-CVE-2023-6516 |
| Debian:12 | bind9 | 1:9.17.19-1 | DEBIAN-CVE-2023-6516 |
| Debian:13 | bind9 | 1:9.17.19-1 | DEBIAN-CVE-2023-6516 |
| Debian:14 | bind9 | 1:9.17.19-1 | DEBIAN-CVE-2023-6516 |
| Rocky Linux:9 | bind | 2:9.16.23-18.el9_4.1 | RLSA-2024:2551 |
| Rocky Linux:9 | bind-dyndb-ldap | 0:11.9-9.el9_4 | RLSA-2024:2551 |
| Rocky Linux:8 | bind9.16 | 2:9.16.23-0.16.el8_9.2 | RLSA-2024:1781 |
Affected products (as reported)
Weakness: CWE-789 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- CVE-2023-6516 vendor-advisory
- http://www.openwall.com/lists/oss-security/2024/02/13/1
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/
- https://security.netapp.com/advisory/ntap-20240503-0008/