CVE-2018-19396

Exp

ext/standard/var_unserializer.c in PHP 5.x through 7.1.24 allows attackers to cause a denial of service (application crash) via an unserialize call for the com, dotnet, or variant class.

Published: 2018-11-20 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-19396 is rated High Exploit Risk (80.2/100): CVSS High severity, with high exploitation likelihood (EPSS 4.58%, 90th percentile). 1 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +3.56% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2018-19396

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2018-19396

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 1.02% 4.58% +3.56%
2 2026-05-29 1.92% 1.02% -0.89%
3 2026-03-04 — 1.92% —

Full EPSS history (36 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-19396

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-2018-19396

OS Trackers for CVE-2018-19396

vendor priority summary link
redhat low — https://access.redhat.com/security/cve/CVE-2018-19396
ubuntu medium CVE-2018-19396 medium priority: Ubuntu including 3 source packages (php5, php7.0, php7.2), 15 status rows across 5 suites (bionic, cosmic, trusty, upstream, xenial): DNE 8, not-affected 4, needs-triage 3. https://ubuntu.com/security/CVE-2018-19396

Affected software / configurations for CVE-2018-19396

Vendor Product Version Raw CPE
php php >= 5.0.0, <= 7.1.24 cpe:2.3:a:php:php:*:*:*:*:*:*:*:*

References for CVE-2018-19396

URL Tags
http://www.securityfocus.com/bid/105989 Third Party Advisory VDB Entry
https://bugs.php.net/bug.php?id=77177 Exploit Issue Tracking Mailing List Vendor Advisory
https://security.netapp.com/advisory/ntap-20181221-0005/ Third Party Advisory
cvelogic Threat Intelligence