IBM Informix Dynamic Server 14.10 is vulnerable to a stack based buffer overflow, caused by improper bounds checking.

published 2021-04-30 5y ago modified 2026-06-17 4mo ago also EUVD-2021-7933

cvss: 6.7; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits: 0; none known

IBM Informix Dynamic Server 14.10 is vulnerable to a stack based buffer overflow, caused by improper bounds checking. A local privileged user could overflow a buffer and execute arbitrary code on the system or cause a denial of service condition. IBM X-Force ID: 198366.

Patch / fix

links 1

ibm.com/support/pages/node/6448568 advisory

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Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.0	6.7	CVSS:3.0/C:H/S:U/PR:H/A:H/AV:L/UI:N/I:H/AC:L/RL:O/RC:C/E:U
NVD	3.1	6.7	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CNA	3.0	6.7	CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	4.6	AV:L/AC:L/Au:N/C:P/I:P/A:P

Affected products

IBM Informix Dynamic Server

Classification

Weakness

CWE-787 Out-of-bounds Write

References

ibm.com /support/pages/node/6448568
patch, vendor-advisory
exchange.xforce.ibmcloud.com /vulnerabilities/198366
vdb-entry, vendor-advisory

Sources

CVE List CVE-2021-20515
NVD CVE-2021-20515

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