UnratedFix available
Fix CVE(s): CVE-2023-6516
Type: advisorySources: OSV
* SECURITY UPDATE: unbounded growth of the asynchronous RBT cache-cleanup queue lets max-cache-size be exceeded - debian/patches/CVE-2023-6516.patch: limit isc_task_send() overhead for tree pruning (upstream c3377cbfaa). - debian/patches/CVE-2023-6516-lock-contention.patch: reduce lock contention during RBTDB tree pruning (upstream 801e888d03). - debian/patches/CVE-2023-6516-prune-guards.patch: guard re-queueing a node for pruning (upstream f6289ad931, 4b6fc97af6, 7d9be24bb1). - debian/patches/CVE-2023-6516-final-design.patch: the design upstream settled on in 9.16.49, GL #4621 (upstream a548312191, eba7fb5f9f, 5f98eba608). Drops the prunenodes lists, so dns_rbtnode is unchanged and MAPAPI stays at 1.0. - CVE-2023-6516
- Products
- bind9, bind9-doc, bind9-host, bind9utils, dnsutils, libbind-dev, libbind-export-dev, libbind9-160, libdns-export1100, libdns1100, libirs-export160, libirs160, libisc-export169, libisc169, libisccc-export160, libisccc160, libisccfg-export160, libisccfg160, liblwres160
- Affected versions
- Not specified
- Fixed versions
- 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
- CVEs
- CVE-2023-6516
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 11:41 UTC · Revision 1
Source evidence
* SECURITY UPDATE: unbounded growth of the asynchronous RBT cache-cleanup queue lets max-cache-size be exceeded - debian/patches/CVE-2023-6516.patch: limit isc_task_send() overhead for tree pruning (upstream c3377cbfaa). - debian/patches/CVE-2023-6516-lock-contention.patch: reduce lock contention during RBTDB tree pruning (upstream 801e888d03). - debian/patches/CVE-2023-6516-prune-guards.patch: guard re-queueing a node for pruning (upstream f6289ad931, 4b6fc97af6, 7d9be24bb1). - debian/patches/CVE-2023-6516-final-design.patch: the design upstream settled on in 9.16.49, GL #4621 (upstream a548312191, eba7fb5f9f, 5f98eba608). Drops the prunenodes lists, so dns_rbtnode is unchanged and MAPAPI stays at 1.0. - CVE-2023-6516
osv:CLSA-2026-1788000191
bind9
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
bind9-doc
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
bind9-host
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
bind9utils
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
dnsutils
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libbind-dev
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libbind-export-dev
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libbind9-160
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libdns-export1100
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libdns1100
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libirs-export160
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libirs160
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libisc-export169
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libisc169
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libisccc-export160
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libisccc160
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libisccfg-export160
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
libisccfg160
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
liblwres160
Fixed versions: 1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11
Complete source record
{
"id": "e8a4b6d4d621325e64ec98e651177ba8a46a6c77c74fa2e1b0f36cca99409191",
"url": "https://osv.dev/vulnerability/CLSA-2026-1788000191",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Fix CVE(s): CVE-2023-6516",
"summary": "* SECURITY UPDATE: unbounded growth of the asynchronous RBT cache-cleanup queue lets max-cache-size be exceeded - debian/patches/CVE-2023-6516.patch: limit isc_task_send() overhead for tree pruning (upstream c3377cbfaa). - debian/patches/CVE-2023-6516-lock-contention.patch: reduce lock contention during RBTDB tree pruning (upstream 801e888d03). - debian/patches/CVE-2023-6516-prune-guards.patch: guard re-queueing a node for pruning (upstream f6289ad931, 4b6fc97af6, 7d9be24bb1). - debian/patches/CVE-2023-6516-final-design.patch: the design upstream settled on in 9.16.49, GL #4621 (upstream a548312191, eba7fb5f9f, 5f98eba608). Drops the prunenodes lists, so dns_rbtnode is unchanged and MAPAPI stays at 1.0. - CVE-2023-6516",
"evidence": "osv:CLSA-2026-1788000191",
"products": [
{
"name": {
"value": "bind9",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "bind9-doc",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "bind9-host",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "bind9utils",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/3/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "dnsutils",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/4/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libbind-dev",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/5/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libbind-export-dev",
"evidence": "/affected/6/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/6/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libbind9-160",
"evidence": "/affected/7/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/7/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libdns-export1100",
"evidence": "/affected/8/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/8/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libdns1100",
"evidence": "/affected/9/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/9/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libirs-export160",
"evidence": "/affected/10/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/10/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libirs160",
"evidence": "/affected/11/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/11/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libisc-export169",
"evidence": "/affected/12/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/12/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libisc169",
"evidence": "/affected/13/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/13/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libisccc-export160",
"evidence": "/affected/14/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/14/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libisccc160",
"evidence": "/affected/15/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/15/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libisccfg-export160",
"evidence": "/affected/16/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/16/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libisccfg160",
"evidence": "/affected/17/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/17/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "liblwres160",
"evidence": "/affected/18/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11",
"evidence": "/affected/18/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "CLSA-2026-1788000191",
"aliases": [
"CLSA-2026-1788000191"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "bind9",
"purl": "pkg:deb/tuxcare/bind9?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "bind9-doc",
"purl": "pkg:deb/tuxcare/bind9-doc?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "bind9-host",
"purl": "pkg:deb/tuxcare/bind9-host?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "bind9utils",
"purl": "pkg:deb/tuxcare/bind9utils?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "dnsutils",
"purl": "pkg:deb/tuxcare/dnsutils?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libbind-dev",
"purl": "pkg:deb/tuxcare/libbind-dev?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libbind-export-dev",
"purl": "pkg:deb/tuxcare/libbind-export-dev?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libbind9-160",
"purl": "pkg:deb/tuxcare/libbind9-160?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libdns-export1100",
"purl": "pkg:deb/tuxcare/libdns-export1100?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libdns1100",
"purl": "pkg:deb/tuxcare/libdns1100?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libirs-export160",
"purl": "pkg:deb/tuxcare/libirs-export160?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libirs160",
"purl": "pkg:deb/tuxcare/libirs160?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libisc-export169",
"purl": "pkg:deb/tuxcare/libisc-export169?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libisc169",
"purl": "pkg:deb/tuxcare/libisc169?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libisccc-export160",
"purl": "pkg:deb/tuxcare/libisccc-export160?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libisccc160",
"purl": "pkg:deb/tuxcare/libisccc160?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libisccfg-export160",
"purl": "pkg:deb/tuxcare/libisccfg-export160?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "libisccfg160",
"purl": "pkg:deb/tuxcare/libisccfg160?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.11.3+dfsg-1ubuntu1.18+tuxcare.els11"
}
]
}
],
"package": {
"name": "liblwres160",
"purl": "pkg:deb/tuxcare/liblwres160?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788000191.json"
}
}
],
"modified": "2026-10-26T09:32:03.775864419Z",
"provider": "osv",
"upstream": [
"CVE-2023-6516"
],
"references": [
"https://errata.tuxcare.com/els_os/ubuntu18.04els/CLSA-2026-1788000191.html",
"https://nvd.nist.gov/vuln/detail/CVE-2023-6516"
]
},
"related_cves": [
{
"value": "CVE-2023-6516",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 449552,
"published_at": "2026-08-29T10:48:19+00:00"
}