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TI-2023-05972 Aliases CVE-2023-6516GHSA-8mxm-4gjm-vrc7

Specific recursive query patterns may lead to an out-of-memory condition

Priority MEDIUM 41CWE-789Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-789.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01097 65th percentileScored 2026-11-07
Fix Fixed Red Hat: 7 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ISCBIND 99.16.0 – 9.16.45; 9.16.8-S1 – 9.16.45-S1—No fix listedCNA
  • BIND 9 VendorISC Affected 9.16.0 – 9.16.45; 9.16.8-S1 – 9.16.45-S1 Fixed in — No fix listed CNA

CPE configurations NVD · 12

CPEVersionsRoleVendor
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*9.16.0 – 9.16.45VulnerableISC
cpe:2.3:a:isc:bind:9.16.8:s1:*:*:supported_preview:*:*:*9.16.8 s1VulnerableISC
cpe:2.3:a:isc:bind:9.16.11:s1:*:*:supported_preview:*:*:*9.16.11 s1VulnerableISC
cpe:2.3:a:isc:bind:9.16.12:s1:*:*:supported_preview:*:*:*9.16.12 s1VulnerableISC
cpe:2.3:a:isc:bind:9.16.13:s1:*:*:supported_preview:*:*:*9.16.13 s1VulnerableISC
cpe:2.3:a:isc:bind:9.16.14:s1:*:*:supported_preview:*:*:*9.16.14 s1VulnerableISC
cpe:2.3:a:isc:bind:9.16.21:s1:*:*:supported_preview:*:*:*9.16.21 s1VulnerableISC
cpe:2.3:a:isc:bind:9.16.32:s1:*:*:supported_preview:*:*:*9.16.32 s1VulnerableISC
cpe:2.3:a:isc:bind:9.16.36:s1:*:*:supported_preview:*:*:*9.16.36 s1VulnerableISC
cpe:2.3:a:isc:bind:9.16.43:s1:*:*:supported_preview:*:*:*9.16.43 s1VulnerableISC
  • cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* Versions 9.16.0 – 9.16.45 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.8:s1:*:*:supported_preview:*:*:* Versions 9.16.8 s1 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.11:s1:*:*:supported_preview:*:*:* Versions 9.16.11 s1 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.12:s1:*:*:supported_preview:*:*:* Versions 9.16.12 s1 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.13:s1:*:*:supported_preview:*:*:* Versions 9.16.13 s1 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.14:s1:*:*:supported_preview:*:*:* Versions 9.16.14 s1 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.21:s1:*:*:supported_preview:*:*:* Versions 9.16.21 s1 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.32:s1:*:*:supported_preview:*:*:* Versions 9.16.32 s1 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.36:s1:*:*:supported_preview:*:*:* Versions 9.16.36 s1 Vulnerable ·ISC
  • cpe:2.3:a:isc:bind:9.16.43:s1:*:*:supported_preview:*:*:* Versions 9.16.43 s1 Vulnerable ·ISC
Show 2 more CPE
CPEVersionsRoleVendor
cpe:2.3:a:isc:bind:9.16.45:s1:*:*:supported_preview:*:*:*9.16.45 s1VulnerableISC
cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*not specified by NVDVulnerableNetApp
  • cpe:2.3:a:isc:bind:9.16.45:s1:*:*:supported_preview:*:*:* Versions 9.16.45 s1 Vulnerable ·ISC
  • cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:* Versions not specified by NVD Vulnerable ·NetApp

Remediation

Red Hat 7 advisories

  • RHSA-2024:2551 Released 2024-04-30 · Red Hat rating Important
    bind security update
    • Red Hat Enterprise Linux AppStream (v. 9) bind-32:9.16.23-18.el9_4.1, bind-chroot-32:9.16.23-18.el9_4.1, bind-dnssec-doc-32:9.16.23-18.el9_4.1 +6
    • Red Hat Enterprise Linux CRB (v. 9) bind-devel-32:9.16.23-18.el9_4.1, bind-doc-32:9.16.23-18.el9_4.1, bind-libs-32:9.16.23-18.el9_4.1
  • RHSA-2024:1803 Released 2024-04-15 · Red Hat rating Important
    bind and bind-dyndb-ldap security updates
    • Red Hat CodeReady Linux Builder EUS (v.9.2) bind-devel-32:9.16.23-11.el9_2.4, bind-doc-32:9.16.23-11.el9_2.4, bind-libs-32:9.16.23-11.el9_2.4
    • Red Hat Enterprise Linux AppStream EUS (v.9.2) bind-32:9.16.23-11.el9_2.4, bind-chroot-32:9.16.23-11.el9_2.4, bind-dnssec-doc-32:9.16.23-11.el9_2.4 +6
  • RHSA-2024:1800 Released 2024-04-15 · Red Hat rating Important
    bind and bind-dyndb-ldap security updates
    • Red Hat CodeReady Linux Builder EUS (v.9.0) bind-devel-32:9.16.23-1.el9_0.5, bind-libs-32:9.16.23-1.el9_0.5
    • Red Hat Enterprise Linux AppStream EUS (v.9.0) bind-32:9.16.23-1.el9_0.5, bind-chroot-32:9.16.23-1.el9_0.5, bind-dnssec-doc-32:9.16.23-1.el9_0.5 +6
Show 4 more Red Hat advisories
  • RHSA-2024:1789 Released 2024-04-11 · Red Hat rating Important
    bind security update
    • Red Hat CodeReady Linux Builder (v. 9) bind-devel-32:9.16.23-14.el9_3.4, bind-doc-32:9.16.23-14.el9_3.4, bind-libs-32:9.16.23-14.el9_3.4
    • Red Hat Enterprise Linux AppStream (v. 9) bind-32:9.16.23-14.el9_3.4, bind-chroot-32:9.16.23-14.el9_3.4, bind-dnssec-doc-32:9.16.23-14.el9_3.4 +6
  • RHSA-2024:1781 Released 2024-04-11 · Red Hat rating Important
    bind9.16 security update
    • Red Hat CodeReady Linux Builder (v. 8) bind9.16-devel-32:9.16.23-0.16.el8_9.2, bind9.16-doc-32:9.16.23-0.16.el8_9.2, bind9.16-libs-32:9.16.23-0.16.el8_9.2
    • Red Hat Enterprise Linux AppStream (v. 8) bind9.16-32:9.16.23-0.16.el8_9.2, bind9.16-chroot-32:9.16.23-0.16.el8_9.2, bind9.16-dnssec-utils-32:9.16.23-0.16.el8_9.2 +4
  • RHSA-2024:1648 Released 2024-04-02 · Red Hat rating Important
    bind9.16 security update
    • Red Hat CodeReady Linux Builder EUS (v.8.8) bind9.16-devel-32:9.16.23-0.14.el8_8.4, bind9.16-doc-32:9.16.23-0.14.el8_8.4, bind9.16-libs-32:9.16.23-0.14.el8_8.4
    • Red Hat Enterprise Linux AppStream EUS (v.8.8) bind9.16-32:9.16.23-0.14.el8_8.4, bind9.16-chroot-32:9.16.23-0.14.el8_8.4, bind9.16-dnssec-utils-32:9.16.23-0.14.el8_8.4 +4
  • RHSA-2024:1647 Released 2024-04-02 · Red Hat rating Important
    bind9.16 security update
    • Red Hat CodeReady Linux Builder EUS (v.8.6) bind9.16-devel-32:9.16.23-0.7.el8_6.5, bind9.16-dnssec-utils-32:9.16.23-0.7.el8_6.5, bind9.16-doc-32:9.16.23-0.7.el8_6.5 +2
    • Red Hat Enterprise Linux AppStream EUS (v.8.6) bind9.16-32:9.16.23-0.7.el8_6.5, bind9.16-chroot-32:9.16.23-0.7.el8_6.5, bind9.16-libs-32:9.16.23-0.7.el8_6.5 +2

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2024:1781
Red Hat CodeReady Linux Builder (v. 9)Fixed RHSA-2024:1789
Red Hat CodeReady Linux Builder EUS (v.8.6)Fixed RHSA-2024:1647
Red Hat CodeReady Linux Builder EUS (v.8.8)Fixed RHSA-2024:1648
Red Hat CodeReady Linux Builder EUS (v.9.0)Fixed RHSA-2024:1800
Red Hat CodeReady Linux Builder EUS (v.9.2)Fixed RHSA-2024:1803
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2024:1781
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2024:1789, RHSA-2024:2551
Red Hat Enterprise Linux AppStream EUS (v.8.6)Fixed RHSA-2024:1647
Red Hat Enterprise Linux AppStream EUS (v.8.8)Fixed RHSA-2024:1648
Red Hat Enterprise Linux AppStream EUS (v.9.0)Fixed RHSA-2024:1800
Red Hat Enterprise Linux AppStream EUS (v.9.2)Fixed RHSA-2024:1803
Red Hat Enterprise Linux CRB (v. 9)Fixed RHSA-2024:2551
Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-6516
  2. 2026-10-03 Alias added: GHSA-8mxm-4gjm-vrc7

References

Advisory 5

  • TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
  • TI-2023-27571 Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related… CVSS 3.1HIGH 7.5
  • TI-2021-07476 A second vulnerability in BIND's GSSAPI security policy negotiation can be targeted by a buffer overflow attack CVSS 3.1CRITICAL 9.8
  • TI-2023-27773 The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance… CVSS 3.1HIGH 7.5
  • TI-2020-06910 A logic error in code which checks TSIG validity can be used to trigger an assertion failure in tsig.c CVSS 3.1HIGH 7.5
  • TI-2016-02320 buffer.c in named in ISC BIND 9 before 9.9.9-P3, 9.10.x before 9.10.4-P3, and 9.11.x… CVSS 3.0HIGH 7.5
See all 192 →

Sources

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