CVE-2026-16439

CRITICALNVD 9.19.1
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

Score 9.1 from GitHub Security Advisory published 2026-07-21. NVD baseline CVSS 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this week

Also known asEUVD-2026-46338 (ENISA EUVD) · GHSA-pw53-4wcc-wm6v (GitHub Security Advisories)Source: ENISA EUVD

9.1EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 9.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

In Eclipse OpenJ9 versions up to 0.60, using -Xtrace to trace method arguments can lead to buffer underflow.

CVSS v3
9.1
EG Score
9.1CRITICALmedium confidence
EG Risk
41
EG Risk 41/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity91% × 45%
Impact severity (EG Severity): CVSS 9.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.4% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.4%
EPSS %ILE
37th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.1): severity, escalated by confirmed exploitation. This CVE's 9.1 is its impact severity (EG Severity), not escalated.

EG Severity
9.1 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 21, 2026

Last Modified

October 24, 2026

Advisory Details (2)

Auto-updated Sep 16, 2026
Patch available. Sources: github_pr.
Web page

Eclipse Projects Security / cve-assignment · GitLab

https://gitlab.eclipse.org/security/cve-assignment/-/work_items/192
GitHub pull request

(0.60) Fix bug causing null to be written before the allocated buffer start

Fix merged in eclipse-openj9/openj9 PR #24394 on 2026-07-21 — awaiting tagged release

https://github.com/eclipse-openj9/openj9/pull/24394

Patch Availability(2)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatjava-21-ibm-semeru-certified-jdk-1:21.0.12.0.8-1.el10_02026-08-10redhat
redhatjava-1.8.0-ibm-1:1.8.0.8.70-1.el8_102026-08-10redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 31× in last 7d / 102× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 519 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 419 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-30 08:23 UTCEG score recompute
  2. 2026-10-30 08:23 UTCVendor advisory
  3. 2026-10-30 08:23 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  4. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  5. 2026-10-29 09:58 UTCEG score recompute
  6. 2026-10-29 09:58 UTCVendor advisory
  7. 2026-10-29 09:58 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  8. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  9. 2026-10-28 11:34 UTCEG score recompute
  10. 2026-10-28 11:34 UTCVendor advisory
  11. 2026-10-28 11:34 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  12. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  13. 2026-10-27 12:49 UTCVendor advisory
  14. 2026-10-27 12:49 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  15. 2026-10-26 16:46 UTCEG score recompute
  16. 2026-10-26 16:46 UTCVendor advisory
  17. 2026-10-26 16:46 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  18. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  19. 2026-10-25 18:09 UTCEG score recompute
  20. 2026-10-25 18:09 UTCVendor advisory
  21. 2026-10-25 18:09 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  22. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  23. 2026-10-25 14:46 UTCEG score recompute
  24. 2026-10-24 19:26 UTCEG score recompute
  25. 2026-10-24 19:26 UTCVendor advisory
Show 75 more
  1. 2026-10-24 19:26 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  2. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  3. 2026-10-24 01:08 UTCEG score recompute
  4. 2026-10-24 01:08 UTCVendor advisory
  5. 2026-10-24 01:08 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  6. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  7. 2026-10-23 02:42 UTCEG score recompute
  8. 2026-10-23 02:42 UTCVendor advisory
  9. 2026-10-23 02:42 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  10. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  11. 2026-10-22 04:14 UTCEG score recompute
  12. 2026-10-22 04:14 UTCVendor advisory
  13. 2026-10-22 04:14 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  14. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  15. 2026-10-21 05:38 UTCEG score recompute
  16. 2026-10-21 05:38 UTCVendor advisory
  17. 2026-10-21 05:38 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  18. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  19. 2026-10-20 07:13 UTCEG score recompute
  20. 2026-10-20 07:13 UTCVendor advisory
  21. 2026-10-20 07:13 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  22. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  23. 2026-10-19 08:40 UTCEG score recompute
  24. 2026-10-19 08:40 UTCVendor advisory
  25. 2026-10-19 08:40 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  26. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  27. 2026-10-18 10:13 UTCVendor advisory
  28. 2026-10-18 10:13 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  29. 2026-10-18 04:00 UTCEG score recompute
  30. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  31. 2026-10-17 06:30 UTCEG score recompute
  32. 2026-10-17 06:30 UTCVendor advisory
  33. 2026-10-17 06:30 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  34. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  35. 2026-10-16 07:58 UTCEG score recompute
  36. 2026-10-16 07:58 UTCVendor advisory
  37. 2026-10-16 07:58 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  38. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  39. 2026-10-15 07:00 UTCEG score recompute
  40. 2026-10-15 07:00 UTCVendor advisory
  41. 2026-10-15 07:00 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  42. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  43. 2026-10-14 02:49 UTCEG score recompute
  44. 2026-10-14 02:49 UTCVendor advisory
  45. 2026-10-14 02:48 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  46. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  47. 2026-10-12 22:55 UTCEG score recompute
  48. 2026-10-12 22:55 UTCVendor advisory
  49. 2026-10-12 22:55 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  50. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  51. 2026-10-12 16:30 UTCEG score recompute
  52. 2026-10-12 09:35 UTCVendor advisory
  53. 2026-10-12 09:34 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  54. 2026-10-11 20:09 UTCEG score recompute
  55. 2026-10-11 17:21 UTCEG score recompute
  56. 2026-10-11 14:54 UTCEG score recompute
  57. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  58. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  59. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  60. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  61. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  62. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  63. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  64. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  65. 2026-10-04 14:49 UTCEG score recompute
  66. 2026-10-04 14:49 UTCVendor advisory
  67. 2026-10-04 14:49 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  68. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  69. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  70. 2026-10-01 15:53 UTCVendor advisory
  71. 2026-10-01 15:53 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  72. 2026-10-01 11:29 UTCVendor advisory
  73. 2026-10-01 11:29 UTCGHSA enrichmentGHSA-pw53-4wcc-wm6v · GitHub CVSS 9.1
  74. 2026-10-01 07:29 UTCEG score recompute
  75. 2026-10-01 07:29 UTCVendor advisory

Frequently asked(5)

What is CVE-2026-16439?
CVE-2026-16439 is a critical-severity vulnerability; its CVE record was published on July 21, 2026. In Eclipse OpenJ9 versions up to 0.60, using -Xtrace to trace method arguments can lead to buffer underflow.
When was the CVE record for CVE-2026-16439 published?
The CVE record for CVE-2026-16439 was published on July 21, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 24, 2026; the record at its source may have been updated since.
Is CVE-2026-16439 actively exploited?
CVE-2026-16439 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (37th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-16439?
CVE-2026-16439 has a CVSS v3 base score of 9.1 (NVD).
How do I remediate CVE-2026-16439?
A fix for CVE-2026-16439 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-16439 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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