CVE-2018-21029: Critical severity systemd vulnerability

Published Oct 30, 2019
·
Updated

DISPUTED systemd 239 through 245 accepts any certificate signed by a trusted certificate authority for DNS Over TLS. Server Name Indication (SNI) is not sent, and there is no hostname validation with the GnuTLS backend. NOTE: This has been disputed by the developer as not a vulnerability since hostname validation does not have anything to do with this issue (i.e. there is no hostname to be sent).

Affected Software

2 affected components
Systemd Project Systemd>=239<244
Fedoraproject Fedora=31

Event History

Oct 30, 2019
CVE Published
via MITRE·09:46 PM
Data Sourced
via MITRE·09:46 PM
Description
Disputed
10:15 PM

Frequently Asked Questions

1

What is CVE-2018-21029?

CVE-2018-21029 is a vulnerability in systemd versions 239 through 245 that allows the acceptance of any certificate signed by a trusted certificate authority for DNS Over TLS without proper hostname validation.

2

Is CVE-2018-21029 a critical vulnerability?

Yes, CVE-2018-21029 has a severity keyword of 'critical' and a severity value of 9.8.

3

How does CVE-2018-21029 affect systemd?

CVE-2018-21029 affects systemd versions 239 through 245 and allows the acceptance of any certificate signed by a trusted certificate authority for DNS Over TLS without proper hostname validation.

4

What is the impact of CVE-2018-21029?

The impact of CVE-2018-21029 is that an attacker could use a malicious certificate to perform man-in-the-middle attacks on DNS traffic.

5

How can CVE-2018-21029 be mitigated?

To mitigate CVE-2018-21029, it is recommended to update systemd to a version that includes the fix for the vulnerability.

Contact

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