cbcvebase.
CVE-2017-9445
published 2017-06-28

CVE-2017-9445: In systemd through 233, certain sizes passed to dns_packet_new in systemd-resolved can cause it to allocate a buffer that's too small. A malicious DNS server…

PriorityP359high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
55.12%
98.9th percentile
In systemd through 233, certain sizes passed to dns_packet_new in systemd-resolved can cause it to allocate a buffer that's too small. A malicious DNS server can exploit this via a response with a specially crafted TCP payload to trick systemd-resolved into allocating a buffer that's too small, and subsequently write arbitrary data beyond the end of it.

Affected

6 ranges
VendorProductVersion rangeFixed in
debiansystemd< systemd 233-10 (bookworm)systemd 233-10 (bookworm)
systemd_projectsystemd>= 0 < 233-10233-10
systemd_projectsystemd>= 0 < 233-10233-10
systemd_projectsystemd>= 0 < 233-10233-10
systemd_projectsystemd>= 0 < 233-10233-10
systemd_projectsystemd223 – 233

Detection & IOCsextracted from sources · hover to see the quote

  • The vulnerability is triggered via a specially crafted DNS response over TCP; monitor for anomalous or oversized DNS TCP payloads sent to hosts running systemd-resolved.
  • The vulnerable function is dns_packet_new in systemd-resolved; crash or unexpected termination of the systemd-resolved daemon process may indicate exploitation attempts.
  • Exploitation can result in daemon crash or arbitrary code execution in the context of the systemd-resolved process; alert on unexpected crashes or restarts of systemd-resolved.
  • ·Red Hat Enterprise Linux 7 ships a version of systemd that is NOT affected by this CVE; detection efforts should focus on other distributions (e.g., Ubuntu, Fedora, Debian) running systemd through version 233.
  • ·The vulnerability is fixed in systemd 233-10 on Debian-based systems; ensure patched versions are deployed before deprioritizing detection coverage.

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
vendor_ubuntu7.5HIGH
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