CVE-2016-9584

libical allows remote attackers to cause a denial of service (use-after-free) and possibly read heap memory via a crafted ics file.

Published: 2017-01-18 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-9584 is rated High Risk (65.6/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 2.06%). EPSS rose +1.64% 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-2016-9584

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 0.42% 2.06% +1.64%
2 2026-05-02 0.78% 0.42% -0.36%
3 2025-06-19 — 0.78% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-9584

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.0 CRITICAL
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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:H)
Serious risk that confidential data gets exposed in a big 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 5.2 [email protected]
6.4 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/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:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 4.9 [email protected]

Weakness enumeration for CVE-2016-9584

OS Trackers for CVE-2016-9584

vendor priority summary link
debian not yet assigned CVE-2016-9584 not yet assigned priority: Debian including 1 source packages (libical3), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2016-9584
redhat medium — https://access.redhat.com/security/cve/CVE-2016-9584
suse medium CVE-2016-9584 severity moderate: SUSE including 43 source package names (libical-devel-0.43-1.10.6.1, libical-devel-1.0.1-16.3.1, …), 83 product×package rows across 43 product lines (SUSE Linux Enterprise Desktop 12 SP2, SUSE Linux Enterprise Desktop 12 SP3, … (43 product lines)): Fixed 83. https://www.suse.com/security/cve/CVE-2016-9584/
ubuntu low CVE-2016-9584 low priority: Ubuntu including 2 source packages (libical, libical3), 44 status rows across 24 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, precise, questing, trusty, upstream, wily, xenial, yakkety, zesty): DNE 17, not-affected 16, ignored 7, needed 2, released 2. https://ubuntu.com/security/CVE-2016-9584

Affected software / configurations for CVE-2016-9584

Vendor Product Version Raw CPE
libical_project libical <= 2.0 cpe:2.3:a:libical_project:libical:*:*:*:*:*:*:*:*

References for CVE-2016-9584

URL Tags
http://www.openwall.com/lists/oss-security/2016/12/15/5 Mailing List Third Party Advisory
http://www.securityfocus.com/bid/94948 Third Party Advisory VDB Entry
cvelogic Threat Intelligence