Vulnerability in Systemd Project
CVE-2018-21029
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)
Vulnerability class: Improper Certificate Validation
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.031 (87.7th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 88th percentile — 87.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.031 · newest: 0.031 · change: 0.000
Affected products
- Systemd Project
- Fedoraproject Fedora — versions 31
Weakness classification (CWE)
References
- github.com/systemd/systemd/issues/9397 (Third Party Advisory, Issue Tracking)
- blog.cloudflare.com/dns-encryption-explained/ (Third Party Advisory)
- github.com/systemd/systemd/blob/v243/src/resolve/resolved-dnstls-gnutls.c (Patch, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- security.netapp.com/advisory/ntap-20191122-0002/ (Third Party Advisory)
- github.com/systemd/systemd/pull/13870 (Patch, Third Party Advisory)
- github.com/systemd/systemd/blob/v243/man/resolved.conf.xml (Exploit, Third Party Advisory)
- github.com/systemd/systemd/blob/v239/man/resolved.conf.xml (Exploit, Third Party Advisory)
- tools.ietf.org/html/rfc7858 (Third Party Advisory)
Frequently asked questions
- What is CVE-2018-21029?
- CVE-2018-21029 is a critical-severity vulnerability in Systemd Project, classified under Improper Certificate Validation. CVSS score: 9.8/10. Published 2019-10-30.
- How severe is CVE-2018-21029?
- Critical severity. CVSS v3 base score is 9.8 out of 10.