CVE-2020-8624 | update-policy rules of type "subdomain" are enforced incorrectly

In BIND 9.9.12 -> 9.9.13, 9.10.7 -> 9.10.8, 9.11.3 -> 9.11.21, 9.12.1 -> 9.16.5, 9.17.0 -> 9.17.3, also affects 9.9.12-S1 -> 9.9.13-S1, 9.11.3-S1 -> 9.11.21-S1 of the BIND 9 Supported Preview Edition, An attacker who has been granted privileges to change a specific subset of the zone's content could abuse these unintended additional privileges to update other contents of the zone.

Published: 2020-08-21 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-8624 is rated Moderate Risk (50/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 3.64%). Core evidence: EPSS rose +2.01% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-8624

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.63% 3.64% +2.01%
2 2026-03-03 1.69% 1.63% -0.05%
3 2025-12-28 1.69%

Full EPSS history (22 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-8624

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 1.4 [email protected]
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 1.4 [email protected]
4.0 2.0 MEDIUM
AV:N/AC:L/Au:S/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
8.0 2.9 [email protected]

Weakness enumeration for CVE-2020-8624

OS Trackers for CVE-2020-8624

vendor priority summary link
alpine medium CVE-2020-8624: 1 source package rows (bind); 57 state rows across 10 repos (3.10-main, 3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 12, open 45. https://security.alpinelinux.org/vuln/CVE-2020-8624
debian not yet assigned CVE-2020-8624 not yet assigned priority: Debian including 1 source packages (bind9), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-8624
gentoo normal CVE-2020-8624: 1 GLSA(s) (202008-19), 1 atom(s) (net-dns/bind); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2020-8624
redhat medium https://access.redhat.com/security/cve/CVE-2020-8624
suse high CVE-2020-8624 severity important: SUSE including 526 source package names (0.1.0:sysuser-shadow-2.0-4.2.8, 0.1.75:sysuser-shadow-2.0-4.2.8, …), 994 product×package rows across 212 product lines (Container bci/bci-init, Container bci/dotnet-aspnet, … (212 product lines)): Fixed 803, Known Affected 157, Known Not Affected 34. https://www.suse.com/security/cve/CVE-2020-8624/
ubuntu low CVE-2020-8624 low priority: Ubuntu including 1 source packages (bind9), 5 status rows across 5 suites (bionic, focal, trusty, upstream, xenial): not-affected 2, released 2, needs-triage 1. https://ubuntu.com/security/CVE-2020-8624

Affected software / configurations for CVE-2020-8624

Vendor Product Version Raw CPE
isc bind >= 9.9.12, <= 9.9.13 cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
isc bind >= 9.10.7, <= 9.10.8 cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
isc bind >= 9.11.3, <= 9.11.21 cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
isc bind >= 9.12.1, <= 9.16.5 cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
isc bind >= 9.17.0, <= 9.17.3 cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
isc bind 9.9.12 cpe:2.3:a:isc:bind:9.9.12:s1:*:*:supported_preview:*:*:*
isc bind 9.9.13 cpe:2.3:a:isc:bind:9.9.13:s1:*:*:supported_preview:*:*:*
isc bind 9.11.3 cpe:2.3:a:isc:bind:9.11.3:s1:*:*:supported_preview:*:*:*
isc bind 9.11.21 cpe:2.3:a:isc:bind:9.11.21:s1:*:*:supported_preview:*:*:*
netapp steelstore_cloud_integrated_storage cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:*
canonical ubuntu_linux 16.04 cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
canonical ubuntu_linux 18.04 cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 20.04 cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
fedoraproject fedora 31 cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
fedoraproject fedora 32 cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
opensuse leap 15.1 cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
opensuse leap 15.2 cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

References for CVE-2020-8624

URL Tags
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.html Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.html Mailing List Third Party Advisory
https://kb.isc.org/docs/cve-2020-8624 Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DQN62GBMCIC5AY4KYADGXNKVY6AJKSJE/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZKAMJZXR66P6S5LEU4SN7USSNCWTXEXP/
https://security.gentoo.org/glsa/202008-19 Third Party Advisory
https://security.netapp.com/advisory/ntap-20200827-0003/ Third Party Advisory
https://usn.ubuntu.com/4468-1/ Third Party Advisory
https://www.debian.org/security/2020/dsa-4752 Third Party Advisory
https://www.synology.com/security/advisory/Synology_SA_20_19 Third Party Advisory
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