Security readout for executives and security teams
Plain-English summary
This flaw can crash affected ISC BIND9 name servers in a narrow zone-transfer condition. It matters mainly for organizations running authoritative DNS on affected BIND versions. The public record does not indicate active exploitation, and the source describes abuse as unlikely because an attacker needs significant zone-content privileges.
Executive priority
Treat this as a targeted availability risk, not a broad internet-wide emergency. Patch affected authoritative DNS infrastructure through normal vulnerability management, faster where DNS availability is business-critical or zone administration is delegated to many users or systems.
Technical view
CVE-2020-8619 is an ISC BIND9 assertion failure in rdataset.c during zone transfer. Exposure requires affected versions and authoritative service for at least one zone containing an empty non-terminal entry with an asterisk character. Impact is denial of service, with CVSS 4.9 and high privileges required.
Likely exposure
Likely exposure is limited to authoritative ISC BIND9 deployments running 9.11.14-9.11.19, 9.16.0-9.16.3, 9.11.14-S1-9.11.19-S1, or 9.14.9-9.14.12. Recursive-only servers and deployments without the described zone-content condition are not indicated as affected by the provided description.
Exploitation context
The source bundle says exploitation would require permission to change zone content and introduce the triggering condition. It also says this vector is unlikely and easily traceable. CISA KEV is false in the provided data, so there is no source-backed evidence here of active exploitation.
Researcher notes
The key gating conditions are authoritative service, affected version range, and specific wildcard-related empty non-terminal zone content. The privilege requirement is high. Public sources in the bundle do not provide exploit details or active exploitation evidence; avoid assuming broader BIND exposure without validating deployment role and zone data.
Mitigation direction
- Upgrade affected ISC BIND9 instances to fixed vendor or distribution packages.
- Prioritize authoritative DNS servers before recursive-only DNS infrastructure.
- Restrict zone-content modification privileges to trusted administrators and controlled automation.
- Review vendor advisories from ISC and your operating-system distributor.
- Monitor DNS service availability until remediation is complete.
Validation and detection
- Inventory BIND9 versions across authoritative DNS servers.
- Confirm whether each server provides authoritative service for any zone.
- Review zone data for empty non-terminal entries containing an asterisk character.
- Verify patched package versions against ISC or distribution advisories.
- Check DNS service logs for assertion failures or unexpected named restarts.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2020-8619 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H1.23.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.9MediumVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://kb.isc.org/docs/cve-2020-8619CVE reference · x_refsource_CONFIRM
- FEDORA-2020-54a91444ffCVE reference · vendor-advisory, x_refsource_FEDORA
- https://security.netapp.com/advisory/ntap-20200625-0003/CVE reference · x_refsource_CONFIRM
- FEDORA-2020-5f8da4b260CVE reference · vendor-advisory, x_refsource_FEDORA
- USN-4399-1CVE reference · vendor-advisory, x_refsource_UBUNTU
- DSA-4752CVE reference · vendor-advisory, x_refsource_DEBIAN
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.