CVE-2016-5826

The parser_get_next_char function in libical 0.47 and 1.0 allows remote attackers to cause a denial of service (out-of-bounds heap read) by crafting a string to the icalparser_parse_string function.

Published: 2017-01-27 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2016-5826 is rated Moderate Risk (55.6/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.76%). 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-2016-5826

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 2025-06-19 0.45% 0.76% +0.31%
2 2025-03-30 1.31% 0.45% -0.86%
3 2025-03-29 1.31%

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-5826

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-2016-5826

OS Trackers for CVE-2016-5826

vendor priority summary link
redhat low https://access.redhat.com/security/cve/CVE-2016-5826
suse medium https://www.suse.com/security/cve/CVE-2016-5826/
ubuntu negligible CVE-2016-5826 negligible priority: Ubuntu including 1 source packages (libical), 24 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 14, ignored 7, needed 2, needs-triage 1. https://ubuntu.com/security/CVE-2016-5826

Affected software / configurations for CVE-2016-5826

Vendor Product Version Raw CPE
libical_project libical 0.47 cpe:2.3:a:libical_project:libical:0.47:*:*:*:*:*:*:*
libical_project libical 1.0 cpe:2.3:a:libical_project:libical:1.0:*:*:*:*:*:*:*

References for CVE-2016-5826

cvelogic Threat Intelligence