CVE-2020-8621

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

Published: Aug 21, 2020Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-617

7.5HIGH

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-617

Affected Products

ISC

commercial·USaka internet systems consortium

bind

Networking Infrastructure

BIND9

Networking Infrastructure

opensuse

oss-project·DE

leapOn-premOS

Operating Systems / linux-distro

Canonical Ltd.

commercial·GBaka canonical

UbuntuOn-premOS

Operating Systems / linux-distro

synology

commercial·USaka diskstation manager (dsm), router manager

dns serverOn-premNetwork Device

Networking Infrastructure / dns-dhcp-ntp

netapp

commercial·US

steelstore cloud integrated storage

Hardware Firmware

Novell Inc.

commercial·US

OpenSUSE LeapOn-premOS

Operating Systems / linux-distro

and 2 more affected products View all →

Exploitability

0 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

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Official Patch Available

Workaround Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Impact

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References

http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.html

lists.opensuse.org

http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.html

lists.opensuse.org

https://kb.isc.org/docs/cve-2020-8621

kb.isc.org

and 5 more references View all →

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