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TI-2020-06914 Aliases CVE-2020-8621GHSA-7vc6-qmjj-2j83

Attempting QNAME minimization after forwarding can lead to an assertion failure in resolver.c

Priority LOW 38CWE-617Published · 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
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-617.

Summary

In BIND 9.14.0 -> 9.16.5, 9.17.0 -> 9.17.3, If a server is configured with both QNAME minimization and 'forward first' then an attacker who can send queries to it may be able to trigger the condition that will cause the server to crash. Servers that 'forward only' are not affected.

Why it matters now

EPSS 0.03065 87th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ISCBIND99.14.0 and later—No fix listedCNA
  • BIND9 VendorISC Affected 9.14.0 and later Fixed in — No fix listed CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*9.14.0 – 9.16.5; 9.17.0 – 9.17.3VulnerableISC
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*15.1VulnerableopenSUSE
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*15.2VulnerableopenSUSE
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*16.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*18.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*20.04VulnerableCanonical
cpe:2.3:a:synology:dns_server:*:*:*:*:*:*:*:*before 2.2.2-5027VulnerableSynology
cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
  • cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:* Versions 9.14.0 – 9.16.5; 9.17.0 – 9.17.3 Vulnerable ·ISC
  • cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* Versions 15.1 Vulnerable ·openSUSE
  • cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:* Versions 15.2 Vulnerable ·openSUSE
  • cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:* Versions 16.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:* Versions 20.04 Vulnerable ·Canonical
  • cpe:2.3:a:synology:dns_server:*:*:*:*:*:*:*:* Versions before 2.2.2-5027 Vulnerable ·Synology
  • cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    ISC BIND9 — GLSA-202008-19

    5 records Highest priority Priority MEDIUM 1 MEDIUM, 4 LOW

    Other records, highest priority first

    • TI-2020-06916 A flaw in native PKCS#11 code can lead to a remotely triggerable assertion failure in pk11.cPriority MEDIUM 42
    • TI-2020-06913 Reachable assertion in ISC BIND9Priority LOW 39
    • TI-2020-06915 A truncated TSIG response can lead to an assertion failurePriority LOW 38
    Show all 5 records → Advisory →
  • Advisory ·

    ISC BIND9 — USN-4468-1

    5 records Highest priority Priority MEDIUM 1 MEDIUM, 4 LOW

    Other records, highest priority first

    • TI-2020-06916 A flaw in native PKCS#11 code can lead to a remotely triggerable assertion failure in pk11.cPriority MEDIUM 42
    • TI-2020-06913 Reachable assertion in ISC BIND9Priority LOW 39
    • TI-2020-06915 A truncated TSIG response can lead to an assertion failurePriority LOW 38
    Show all 5 records → Advisory →

Vendor assessments

Red Hat

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

Not affected: 4 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-8621
  2. 2026-10-03 Alias added: GHSA-7vc6-qmjj-2j83

References

Advisory 7

  • 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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