Attempting QNAME minimization after forwarding can lead to an assertion failure in resolver.c
CVE-2020-8621

7.5HIGH

Key Information:

Vendor
Isc
Status
Vendor
CVE Published:
21 August 2020

Badges

👾 Exploit Exists

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.

Affected Version(s)

BIND9 9.14.0

References

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

ISC would like to thank Joseph Gullo for bringing this vulnerability to our attention.
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