9.4

CVE-2026-16839: Vulnerabilities in IBM AIX and PowerVM VIOS

Analyzed
Published 19-08-2026Last modified 20-08-2026

Vulnerability summary

CVE-2026-16839 is a critical (CVSS 9.4) Out-of-bounds Read vulnerability in ibm aix. EPSS estimates a 0.52% chance of exploitation in the next 30 days, higher than 43.4% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.4/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.52%
0%100%
Low · +0.14 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 19-08-2026
    PublishedVulnerability first disclosed.
  2. 20-08-2026
    Last modifiedVulnerability information updated.

Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to obtain sensitive information due to an integer underflow in the IPv4 IP-options parser.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.52%

Chance of exploitation in the next 30 days

Percentile

43%

Versus all other CVEs

30-day change

Increase +0.14 pp

From 0.39% on 22-09-2026

22-09-202622-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ibm3 products
  • aix7.2 | 7.3 | ≥ 7.2.5, ≤ 7.2.5.212 | ≥ 7.3.2, ≤ 7.3.2.5 | ≥ 7.3.3, ≤ 7.3.3.2 | ≥ 7.3.4, ≤ 7.3.4.1
  • powervm vios4.1
  • vios≥ 4.1.0, < 4.1.0.50 | ≥ 4.1.1.0, < 4.1.1.30 | ≥ 4.1.2.0, < 4.1.2.20

1 vendor · 3 products

References

1 links