CVE-2026-44966

CRITICALNVD 9.89.8
EchelonGraph scoreMEDIUM confidence

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

This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 0.5% (45th percentile of EPSS-scored CVEs). GitHub Security Advisory CVSS 8.3 is lower than this score; a lower GitHub score revises it only when its advisory is newer than the CVE record's last change, and this advisory (published 2026-05-09) is not newer than that change (2026-07-24), so it does not.

Triggered by: Headline CVSS from NVD CVSS v3
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 3 sources updated this week

Also known asEUVD-2026-32007 (ENISA EUVD) · GHSA-j658-c2gf-x6pq (GitHub Security Advisories)Source: ENISA EUVD

9.8EG
EchelonGraph verdictPlan mitigationNo fix is confirmed yet: check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 9.8Exploit: None knownExposed services: Not assessed

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

Velocity.js is a JavaScript implementation of the Apache Velocity template engine. In 2.1.5 and earlier, a prototype pollution vulnerability was discovered in velocityjs. This issue occurs during the processing of #set directives in Velocity templates. If an application renders a template controlled by an attacker, it is possible to modify Object.prototype, potentially leading to Denial of Service (DoS) or Remote Code Execution (RCE) depending on the server environment.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
44
EG Risk 44/100

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)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.5% × 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 every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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: No fix is confirmed yet. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule.
EPSS PROB
0.5%
EPSS %ILE
45th
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 (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
0.5% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). 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 every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

No fix is confirmed yet. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (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

May 26, 2026

Last Modified

July 24, 2026

Advisory Details (1)

Auto-updated Oct 31, 2026
🔬 Proof of concept available. No fix on record yet. Sources: github.
GitHub advisoryMentions a patch (unverified)🟡 PoC Available

Prototype Pollution in #set path assignment · Advisory · shepherdwind/velocity.js · GitHub

https://github.com/shepherdwind/velocity.js/security/advisories/GHSA-j658-c2gf-x6pq

Vendor Advisories for CVE-2026-44966(1)

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

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
npmvelocityjs—ghsa

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.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFix by version rangeDependents
velocityjs—
  • every version through 2.1.5: no fix on record
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 19× in last 7d / 74× 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 359 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 259 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-02 16:45 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  2. 2026-11-01 23:13 UTCEG score recompute
  3. 2026-11-01 23:12 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  4. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  5. 2026-10-31 21:26 UTCEG score recompute
  6. 2026-10-31 21:26 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  7. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  8. 2026-10-30 19:41 UTCEG score recompute
  9. 2026-10-30 19:41 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  10. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  11. 2026-10-29 17:50 UTCEG score recompute
  12. 2026-10-29 17:50 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  13. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  14. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  15. 2026-10-28 16:04 UTCEG score recompute
  16. 2026-10-28 16:04 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  17. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  18. 2026-10-27 14:17 UTCEG score recompute
  19. 2026-10-27 14:17 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  20. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  21. 2026-10-26 12:06 UTCEG score recompute
  22. 2026-10-26 12:05 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  23. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  24. 2026-10-25 14:27 UTCEG score recompute
  25. 2026-10-25 10:17 UTCEG score recompute
Show 75 more
  1. 2026-10-25 10:17 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  2. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  3. 2026-10-24 08:31 UTCEG score recompute
  4. 2026-10-24 08:31 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  5. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  6. 2026-10-23 06:45 UTCEG score recompute
  7. 2026-10-23 06:45 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  8. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  9. 2026-10-22 04:59 UTCEG score recompute
  10. 2026-10-22 04:59 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  11. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  12. 2026-10-21 03:10 UTCEG score recompute
  13. 2026-10-21 03:10 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  14. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  15. 2026-10-20 01:22 UTCEG score recompute
  16. 2026-10-20 01:22 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  17. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  18. 2026-10-18 23:35 UTCEG score recompute
  19. 2026-10-18 23:35 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  20. 2026-10-18 03:38 UTCEG score recompute
  21. 2026-10-17 21:48 UTCEG score recompute
  22. 2026-10-17 21:48 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  23. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  24. 2026-10-16 20:02 UTCEG score recompute
  25. 2026-10-16 20:02 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  26. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  27. 2026-10-15 17:36 UTCEG score recompute
  28. 2026-10-15 17:35 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  29. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  30. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  31. 2026-10-14 11:24 UTCEG score recompute
  32. 2026-10-14 11:24 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  33. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  34. 2026-10-13 09:38 UTCEG score recompute
  35. 2026-10-13 09:38 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  36. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  37. 2026-10-12 16:04 UTCEG score recompute
  38. 2026-10-12 07:47 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  39. 2026-10-11 19:47 UTCEG score recompute
  40. 2026-10-11 17:01 UTCEG score recompute
  41. 2026-10-11 14:26 UTCEG score recompute
  42. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  43. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  44. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  45. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  46. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  47. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  48. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  49. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  50. 2026-10-03 19:51 UTCOSV refresh
  51. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  52. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  53. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  54. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  55. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  56. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  57. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  58. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  59. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  60. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  61. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  62. 2026-09-14 09:36 UTCEG score recompute
  63. 2026-09-14 09:36 UTCGHSA enrichmentGHSA-j658-c2gf-x6pq · GitHub severity HIGH · GitHub CVSS 8.3
  64. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  65. 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  66. 2026-09-11 20:10 UTCOSV refresh
  67. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  68. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  69. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  70. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  71. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  72. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  73. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  74. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  75. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.5% · 43rd percentile

Frequently asked(5)

What is CVE-2026-44966?
CVE-2026-44966 is a critical-severity vulnerability; its CVE record was published on May 26, 2026. Velocity.js is a JavaScript implementation of the Apache Velocity template engine. In 2.1.5 and earlier, a prototype pollution vulnerability was discovered in velocityjs. This issue occurs during the processing of #set directives in Velocity templates. If an application renders a template…
When was the CVE record for CVE-2026-44966 published?
The CVE record for CVE-2026-44966 was published on May 26, 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 July 24, 2026; the record at its source may have been updated since.
Is CVE-2026-44966 actively exploited?
CVE-2026-44966 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (45th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-44966?
CVE-2026-44966 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-44966?
No fix for CVE-2026-44966 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-2026-44966 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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