OBS-2026-000229: CVE-2026-91749

1. Observe What changed? →

2. Understand Why does it matter? →

3. Track How does risk evolve? →

4. Predict What happens next? →

5. Decide What to do? →

6. Verify What happened? →

7. Remember Persistent memory

IMMUTABLE CANONICAL OBSERVATION

OBS-2026-000229

Target Entity: CVE-2026-91749 — Google Chrome Workers Subsystem Use-After-Free Remote Code Execution

MODE: RETROSPECTIVE

Methodology: HTS-3.1

Observed UTC:
2026-09-16T00:00:00.000Z

Event Date:
2026-09-16

Epistemic State:
● KNOWN

Cryptographic Digest:
sha256-4d39d00c915a2ae…

1. Verified Evidence & Observed State

This canonical observation confirms the following factual event on the threat surface:

Hermes Threat Score (HTS)

89 / 100

HIGH

CVSS v3.1

8.8

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS (30-Day Exploitation)

11.9%

Percentile: 95.2th

Weaponization & CISA KEV

🛡️ Not in KEV

Exploit Maturity: poc

2. Decomposed Epistemic Confidence Vector

Hermes rejects false certainty and explicitly exposes its decomposed confidence vector:

Evidence Integrity94%

Model Stability96%

Data Completeness95%

Actionable Decisiveness85%

3. Primary Sources & Provenance Chain

Observation OBS-2026-000229 is strictly anchored to verified records from the following primary entities:

NVD CVE-2026-91749 Advisory

Causal Intelligence Lineage

Primary Source → OBS-2026-000229 → CVE-2026-91749 → Risk Trajectory → Action Directive

4. Target Entity & Correlated Intelligence

Primary Vulnerability Dossier: CVE-2026-91749
Impacted Software Product : Google Chromium / V8 (google ecosystem)
Dynamic Risk Trajectories: View risk trajectory analysis
Decision Engine: View prescriptive remediation directives

5. Observation Sequence & Chain of Custody

Chronological lineage for entity CVE-2026-91749:

Preceding Observation: None (Initial Baseline)
Succeeding Observation: OBS-2026-000230

Observation ID	Date	Mode	Score	Observed Fact
👉 `OBS-2026-000229`	`2026-09-16`	RETROSPECTIVE	89	Initial baseline observation created upon public disclosure and ingestion.
`OBS-2026-000230`	`2026-09-22`	LIVE	89	State change observed: threat score adjusted by +0 points; CISA KEV or weaponized exploit verified.

6. Reproducibility & Cryptographic Verification

(Section 77 Mandate: “Observations must be reproducible”)

Fetch and verify this observation record directly from the machine-readable API:

# 1. Fetch canonical observation record
curl -sSL https://hermes-codex.vercel.app/api/observations/OBS-2026-000229.json

# 2. Verify cryptographic SHA-256 integrity
curl -sSL https://hermes-codex.vercel.app/api/observations/OBS-2026-000229.json | sha256sum

OASIS STIX 2.1 Mapping (`observed-data`)

{
  "type": "observed-data",
  "spec_version": "2.1",
  "id": "observed-data--6d0484c1-23ae-5374-17a4-59ef731d6b71",
  "created_by_ref": "identity--hermes-codex-threat-observatory",
  "created": "2026-09-16T00:00:00.000Z",
  "modified": "2026-09-16T00:00:00.000Z",
  "first_observed": "2026-09-16T00:00:00.000Z",
  "last_observed": "2026-09-16T00:00:00.000Z",
  "number_observed": 1,
  "external_references": [
    {
      "source_name": "hermes-codex",
      "external_id": "OBS-2026-000229",
      "url": "https://hermes-codex.vercel.app/observations/obs-2026-000229/"
    }
  ],
  "object_marking_refs": [
    "marking-definition--tlp-clear"
  ],
  "custom_properties": {
    "x_hermes_threat_score": 89,
    "x_hermes_severity": "HIGH",
    "x_hermes_epistemic_state": "KNOWN",
    "x_hermes_methodology": "HTS-3.1",
    "x_hermes_integrity_hash": "sha256-4d39d00c915a2ae125f7bbf83b77c078895b1ce6c3246f7b238a36147033d2ca"
  }
}