CVE-2026-18870

MEDIUMPre-NVD 4.34.3—
EchelonGraph scoreHIGH confidence

Score 4.3 from GitHub Security Advisory published 2026-09-24. A secondary CVSS source baseline 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
4.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 4.3Exploit: None knownExposed services: Not assessed

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

IBM PowerVM Hypervisor FW1120.00 through FW1120.01, FW1110.00 through FW1110.31, FW1060.00 through FW1060.81, and FW950.00 through FW950.H3 could allow a remote attacker to obtain sensitive information due to an out-of-bounds read.

CVSS v3
4.3
EG Score
4.3MEDIUMhigh confidence
EG Risk
24
EG Risk 24/100CISA SSVC

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
Severity43% × 45%
Exploitation0% × 40%
Automatability30% × 15%
CISA SSVC: Track at low or medium mission impact; Track or Attend at high (mission-essential systems).
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
0.2%
EPSS %ILE
7th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track or Attend at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation none (no KEV listing, exploit record or EPSS ≥ 50%) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 24, 2026

Last Modified

September 30, 2026

Advisory Details (1)

Auto-updated Sep 24, 2026
No patch confirmed yet.
generic

Security Bulletin: This Power System update is being released to address CVE-2026-18870

https://www.ibm.com/support/pages/node/7289135

Vendor Advisories for CVE-2026-18870(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 22× in last 7d / 31× 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. 2026-10-04 10:59 UTCEG score recompute
  2. 2026-10-04 10:59 UTCGHSA enrichment
  3. 2026-10-03 12:16 UTCEG score recompute
  4. 2026-10-03 12:16 UTCGHSA enrichment
  5. 2026-10-02 13:33 UTCEG score recompute
  6. 2026-10-02 13:33 UTCGHSA enrichment
  7. 2026-10-01 19:49 UTCEPSS rescore
  8. 2026-10-01 14:48 UTCGHSA enrichment
  9. 2026-09-30 16:05 UTCEG score recompute
  10. 2026-09-30 16:05 UTCGHSA enrichment
  11. 2026-09-30 15:02 UTCEPSS rescore
  12. 2026-09-30 13:04 UTCEG score recompute
  13. 2026-09-30 13:04 UTCGHSA enrichment
  14. 2026-09-29 15:20 UTCEPSS rescore
  15. 2026-09-29 14:19 UTCEG score recompute
  16. 2026-09-29 14:19 UTCGHSA enrichment
  17. 2026-09-28 15:35 UTCEG score recompute
  18. 2026-09-28 15:35 UTCGHSA enrichment
  19. 2026-09-28 13:51 UTCEPSS rescore
  20. 2026-09-27 16:42 UTCEG score recompute
  21. 2026-09-27 16:42 UTCGHSA enrichment
  22. 2026-09-27 13:47 UTCEPSS rescore
  23. 2026-09-26 17:59 UTCEG score recompute
  24. 2026-09-26 17:59 UTCGHSA enrichment
  25. 2026-09-26 15:58 UTCEPSS rescore
Show 6 more
  1. 2026-09-25 19:14 UTCGHSA enrichment
  2. 2026-09-24 19:55 UTCEG score recompute
  3. 2026-09-24 19:55 UTCGHSA enrichment
  4. 2026-09-24 15:28 UTCEG score recompute
  5. 2026-09-24 14:48 UTCEG score recompute
  6. 2026-09-24 14:47 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-18870?
CVE-2026-18870 is a medium vulnerability published on September 24, 2026. IBM PowerVM Hypervisor FW1120.00 through FW1120.01, FW1110.00 through FW1110.31, FW1060.00 through FW1060.81, and FW950.00 through FW950.H3 could allow a remote attacker to obtain sensitive information due to an out-of-bounds read.
When was CVE-2026-18870 disclosed?
CVE-2026-18870 was first published on September 24, 2026, with the most recent update on September 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18870 actively exploited?
CVE-2026-18870 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (7th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-18870?
CVE-2026-18870 has a CVSS base score of 4.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-18870?
No fix for CVE-2026-18870 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-18870 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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