CVE-2018-1636

Stack-based buffer overflow in oninit in IBM Informix Dynamic Server Enterprise Edition 12.1 allows an authenticated user to execute predefined code with root privileges, such as escalating to a root shell. IBM X-Force ID: 144441.

Published: 2019-08-20 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-1636 is rated Low Risk (39.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.44%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2018-1636

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 0.07% 0.44% +0.36%
2 2025-03-30 0.27% 0.07% -0.19%
3 2025-03-29 — 0.27% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-1636

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.7 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:H)
They need powerful rights—admin, root, or similar—before this pays off.
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:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 0.8 5.9 [email protected]
8.2 3.0 HIGH
CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.5 6.0 [email protected]
7.2 2.0 HIGH
AV:L/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 3.9 10.0 [email protected]

Weakness enumeration for CVE-2018-1636

Affected software / configurations for CVE-2018-1636

Vendor Product Version Raw CPE
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc1:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc10:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc11:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc12:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc2:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc3:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc4:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc5:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc6:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc7:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc8:*:*:enterprise:*:*:*
ibm informix_dynamic_server 12.10 cpe:2.3:a:ibm:informix_dynamic_server:12.10:fc9:*:*:enterprise:*:*:*

References for CVE-2018-1636

cvelogic Threat Intelligence