CVE-2016-4574

Off-by-one error in the append_utf8_value function in the DN decoder (dn.c) in Libksba before 1.3.4 allows remote attackers to cause a denial of service (out-of-bounds read) via invalid utf-8 encoded data. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-4356.

Published: 2016-06-13 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2016-4574 is rated Moderate Risk (57.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.09%). Mandatory action: Review affected assets and schedule 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-2016-4574

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 2026-05-13 0.96% 1.09% +0.13%
2 2025-12-28 1.09% 0.96% -0.13%
3 2025-12-27 1.09%

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-4574

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/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-2016-4574

OS Trackers for CVE-2016-4574

vendor priority summary link
debian not yet assigned CVE-2016-4574 not yet assigned priority: Debian including 1 source packages (libksba), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2016-4574
redhat medium https://access.redhat.com/security/cve/CVE-2016-4574
suse high CVE-2016-4574 severity important: SUSE including 261 source package names (0.9.1:libksba8-1.3.0-23.1, 1.0.0:libksba8-1.3.0-23.1, …), 330 product×package rows across 89 product lines (Container caasp/v4/default-http-backend, Container caasp/v4/dnsmasq-nanny, … (89 product lines)): Fixed 173, Known Affected 157. https://www.suse.com/security/cve/CVE-2016-4574/
ubuntu medium CVE-2016-4574 medium priority: Ubuntu including 1 source packages (libksba), 5 status rows across 5 suites (precise, trusty, upstream, wily, xenial): released 5. https://ubuntu.com/security/CVE-2016-4574

Affected software / configurations for CVE-2016-4574

Vendor Product Version Raw CPE
gnupg libksba <= 1.3.3 cpe:2.3:a:gnupg:libksba:*:*:*:*:*:*:*:*
canonical ubuntu_linux 12.04 cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 14.04 cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 15.10 cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:*
canonical ubuntu_linux 16.04 cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
opensuse leap 42.1 cpe:2.3:o:opensuse:leap:42.1:*:*:*:*:*:*:*
opensuse opensuse 13.2 cpe:2.3:o:opensuse:opensuse:13.2:*:*:*:*:*:*:*

References for CVE-2016-4574

cvelogic Threat Intelligence