CVE-2026-16839

CRITICALPre-NVD 9.49.4—
EchelonGraph scoreHIGH confidence

Score 9.4 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-19. a secondary CVSS source baseline 9.4; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
9.4EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.4Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
9.4
EG Score
9.4(high)
EG Risk
58(Track)
EG Risk 58/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity94% × 45%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
42%
KEV
Not listed

Published

August 19, 2026

Last Modified

August 20, 2026

Advisory Details (1)

Auto-updated Aug 19, 2026
No patch confirmed yet.
generic

Security Bulletin: Vulnerabilities in IBM AIX and PowerVM VIOS

https://www.ibm.com/support/pages/node/7283858

Vendor Advisories for CVE-2026-16839(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 17× in last 7d / 17× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-21 05:51 UTCGHSA enrichment
  2. 2026-08-21 01:45 UTCEG score recompute
  3. 2026-08-21 01:45 UTCGHSA enrichment
  4. 2026-08-20 22:55 UTCEPSS rescore
  5. 2026-08-20 21:38 UTCGHSA enrichment
  6. 2026-08-20 17:32 UTCGHSA enrichment
  7. 2026-08-20 13:26 UTCEG score recompute
  8. 2026-08-20 13:26 UTCGHSA enrichment
  9. 2026-08-20 12:42 UTCEG score recompute
  10. 2026-08-20 12:42 UTCGHSA enrichment
  11. 2026-08-20 08:39 UTCGHSA enrichment
  12. 2026-08-20 04:33 UTCGHSA enrichment
  13. 2026-08-20 00:27 UTCEG score recompute
  14. 2026-08-20 00:27 UTCGHSA enrichment
  15. 2026-08-19 20:21 UTCEG score recompute
  16. 2026-08-19 19:43 UTCEG score recompute
  17. 2026-08-19 19:42 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-16839?
CVE-2026-16839 is a critical vulnerability published on August 19, 2026. 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.
When was CVE-2026-16839 disclosed?
CVE-2026-16839 was first published in the National Vulnerability Database on August 19, 2026, with the most recent update on August 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-16839 actively exploited?
CVE-2026-16839 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 57.8% of all scored CVEs.
What is the CVSS score of CVE-2026-16839?
CVE-2026-16839 has a CVSS v3 base score of 9.4 (NVD).
How do I remediate CVE-2026-16839?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-16839, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-16839

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