CVE-2026-16855: CWE-787 Out-of-bounds Write in IBM AIX
Description
CVE-2026-16855 is a vulnerability in IBM AIX versions 7.2 and 7.3, as well as IBM PowerVM VIOS 4.1, involving a heap buffer overflow that can be triggered by a local attacker. This flaw could lead to a denial of service condition. The vulnerability has a medium severity rating with a CVSS score of 5.5. No information about available patches or exploits in the wild is provided.
CVSS v3.1
Score 5.5medium
Affected software
IBM
AIX
IBM
PowerVM VIOS
cpe:2.3:a:ibm:aix:7.2:*:*:*:*:*:*:*cpe:2.3:a:ibm:aix:7.2.0:*:*:*:*:*:*:*cpe:2.3:a:ibm:aix:7.3:*:*:*:*:*:*:*cpe:2.3:a:ibm:aix:7.3.0:*:*:*:*:*:*:*cpe:2.3:a:ibm:powervm_vios:4.1:*:*:*:*:*:*:*cpe:2.3:a:ibm:powervm_vios:4.1.0:*:*:*:*:*:*:*Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, identified as CVE-2026-16855, is a heap buffer overflow (CWE-787) affecting IBM AIX 7.2, 7.3, and IBM PowerVM VIOS 4.1. A local attacker with low privileges could exploit this flaw to cause a denial of service by triggering an out-of-bounds write in heap memory. The CVSS 3.1 base score is 5.5, reflecting a medium severity with local attack vector, low attack complexity, and no impact on confidentiality or integrity but high impact on availability.
Potential Impact
Successful exploitation results in denial of service due to heap buffer overflow. There is no impact on confidentiality or integrity according to the CVSS vector. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch information is provided in the available data. Until a patch is available, restrict local access to trusted users only to mitigate risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- ibm
- Date Reserved
- 2026-07-24T03:32:30.451Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a860991acd9273b498b4c2f
Added to database: 08/19/2026, 19:52:49 UTC
Last enriched: 09/11/2026, 07:48:46 UTC
Last updated: 10/04/2026, 10:02:25 UTC
Views: 41
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