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 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.

Published: 2017-06-28 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-9445 is rated High Risk (69.6/100): CVSS High severity, with high exploitation likelihood (EPSS 55.12%, 99th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +53.79% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-9445

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.33% 55.12% +53.79%
2 2026-05-08 1.70% 1.33% -0.37%
3 2026-02-26 — 1.70% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-9445

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2017-9445

OS Trackers for CVE-2017-9445

vendor priority summary link
debian not yet assigned CVE-2017-9445 not yet assigned priority: Debian including 1 source packages (systemd), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-9445
redhat high — https://access.redhat.com/security/cve/CVE-2017-9445
suse high CVE-2017-9445 severity important: SUSE including 538 source package names (0.9.1:libsystemd0-228-150.9.3, 0.9.1:libudev1-228-150.9.3, …), 671 product×package rows across 58 product lines (Container caasp/v4/default-http-backend, Container caasp/v4/dnsmasq-nanny, … (58 product lines)): Fixed 488, Known Affected 157, Known Not Affected 26. https://www.suse.com/security/cve/CVE-2017-9445/
ubuntu high CVE-2017-9445 high priority: Ubuntu including 1 source packages (systemd), 5 status rows across 5 suites (trusty, upstream, xenial, yakkety, zesty): released 3, needed 1, not-affected 1. https://ubuntu.com/security/CVE-2017-9445

Affected software / configurations for CVE-2017-9445

Vendor Product Version Raw CPE
systemd_project systemd >= 223, <= 233 cpe:2.3:a:systemd_project:systemd:*:*:*:*:*:*:*:*

References for CVE-2017-9445

URL Tags
http://openwall.com/lists/oss-security/2017/06/27/8 Mailing List Patch Third Party Advisory
http://www.securityfocus.com/bid/99302 Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1038806 Third Party Advisory VDB Entry
https://launchpad.net/bugs/1695546 Broken Link
cvelogic Threat Intelligence