CVE-2023-28523: IBM Informix Dynamic Server · Heap-based Buffer Overflow
Affects IBM Informix Dynamic ServerSource CVE Database V5
Not known to be exploited · CVSS 8.4 High.
Data as of 26 Oct 2026, 07:57 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 20% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 9 Dec 2023
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| IBM Informix Dynamic Server | Affected
| Fixed in– |
AI-suggested
European organizations should implement a multi-layered mitigation strategy: 1) Monitor IBM security advisories closely and apply patches or updates as soon as they become available. 2) Restrict local access to Informix servers strictly to trusted administrators and use strong authentication mechanisms to prevent unauthorized access. 3) Employ application whitelisting and endpoint protection solutions to detect and block suspicious activities related to memory corruption exploits. 4) Conduct regular code and configuration audits of Informix deployments to identify and remediate insecure settings. 5) Implement network segmentation to isolate database servers from less trusted network zones, limiting the potential for lateral movement. 6) Use runtime application self-protection (RASP) or memory protection technologies that can detect and prevent heap overflow exploitation attempts. 7) Maintain comprehensive logging and real-time monitoring to detect anomalous behavior indicative of exploitation attempts. These steps go beyond generic advice by focusing on access control, proactive monitoring, and layered defenses tailored to the nature of this heap overflow vulnerability.
Description
IBM Informix Dynamic Server 12.10 and 14.10 onsmsync is vulnerable to a heap buffer overflow, caused by improper bounds checking which could allow an attacker to execute arbitrary code. IBM X-Force ID: 250753.